1 

cThr  i.  1.  HtU  TjJibrarg 

^J^ 

^^^ 

Jfortlj  (Carolina  »mt  Intopraita 

H3 

THIS  BOOR  IS  DUE  ON  THE  DATE 
INDICATED  BELOW  AND  IS  SUB- 
JECT TO  AN  OVERDUE  FINE  AS 
POSTED  AT  THE  CIRCULATION 
DESK. 


THE  PHYLOGENETIC  METHOD  IN  TAXONOMY 


THE  NORTH  AMERICAN  SPECIES  OF  ARTEMISIA,  CHRYSOTHAMNUS, 
AND  ATRIPLEX 


HARVEY  M.  HALL  AND  FREDERIC  E.  CLEMENTS 


Published  bt  the  Carnegie  Institution  of  Washington 
Washington,  1923. 


CARNEGIE  INSTITUTION  OF  WASHINGTON 

Publication  No.  326 


Copies  of  lliis  look 

flrst  issBed 
JUL  20  192.- 


PRESS   OF 
[IDD  &  DETWEILER,  INC. 
WASHINGTON,   D.   C. 


CONTENTS. 


PAGE 

Introduction 3 

Scope  and  duty  of  taxonomy 3 

Scope 3 

Relation  to  ecology  and  experimental  evolution. .  3 

Duty 4 

Scientific  basis  of  taxonomy 4 

Classification  and  relationship 4 

Evolution  and  phylogeny 5 

Synthesis  and  analysis 5 

The  genus  concept 6 

Nature  of  the  genus 6 

Genus  and  section 6 

Generic  segregation 7 

Failures  of  segregation 7 

Proper  treatment  of  genera 8 

The  species  concept 9 

Nature  of  the  species 9 

Definition  of  species 9 

Constancy 10 

Distinctness 10 

Evolutionary  definition 11 

Segregation  of  species 11 

Failures  of  specific  segregation 12 

Scientific  basis  of  species 14 

Nomenclature 16 

Purpose  and  value 16 

Future  role 16 

Essentials  of  stabihty 17 

Practical  nomenclature 17 

A  binomial  system  of  common  names 19 

Methods  and  results  in  evolutionary  taxonomy ....  19 

Methods 19 

Statistics '.  19 

Experiment 20 

Method  of  experiment 21 

Objectives 22 

Variads 23 

Methods  of  treatment 23 

General  plan 23 

Field  work 24 

Results  of  statistical  studies  and  experiments. ...  25 

Illustrations 26 

Phylogenetic  charts 27 

Citation  of  authors,  synonyms,  and  specimens. .  .  27 

Herbaria  studied  and  acknowledgments 28 

References 30 

Genus  Artemisia 31 

Relationships  and  generic  limits 31 

Origin  and  development  of  the  sections 34 

Criteria  for  recognition  of  species  and  subspecies ...  37 

Achene 37 

Style-branches 38 

Corolla 38 

Number  and  reduction  of  flowers  in  the  head ...  39 

Involucre 40 

Inflorescence 40 

Leaves 41 

Stem  and  bark 42 

Roots 43 

Pubescence 43 

Resins,  oils,  and  odors 43 

Habit 43 


PAGE 

Genus  Artemisia — Continued. 

Relative  plasticity  of  the  species 44 

Generic  diagnosis 45 

Key  to  sections  of  Artemisia 46 

Key  to  North  American  species  of  Artemisia 46 

Artificial    key    to    North    American    species    of 

Artemisia 47 

Section  I.     Abrotanum 49 

Phylogeny  of  the  species 49 

1.  Artemisia  abrotanum 49 

Description 49 

Distribution 51 

Minor  variations 51 

Relationships 51 

Ecology  and  uses 51 

2.  Artemisia  pontica 52 

3.  Artemisia  californica 53 

4.  Artemisia  macrobotrys 56 

5.  Artemisia  norvegica 57  . 

6.  Artemisia  senjavinensis 65 

7.  Artemisia  parryi 66 

8.  Artemisia  stelleriana 67 

9.  Artemisia  alaskana 68 

10.  Artemisia  franserioides 69 

11.  Artemisia  vulgaris 71 

12.  Artemisia  biennis 101 

13.  Artemisia  annua 102 

14.  Artemisia  klotzschiana 103 

15.  Artemisia  bigelovi 104 

Section  II.     Absinthium 106 

Phylogeny  of  the  species 106 

16.  Artemisia  absinthium 106 

17.  Artemisia  frigida 108 

18.  Artemisia  scopulorum 110 

19.  Artemisia  pattersoni 112 

Section  III.    Dracunculus 114 

Phylogeny  of  the  species 114 

20.  Artemisia  dracunculus 115 

21.  Artemisia  campestris 120 

22.  Artemisia  filifolia 130 

23.  Artemisia  pedatifida 131 

24.  Artemisia  spinescens 132 

Section  IV.     Seriphidium 134 

Phylogeny  of  the  species 134 

25.  Artemisia  tridentata 135 

26.  Artemisia  cana 150 

27.  Artemisia  rigida 153 

28.  Artemisia  pygmaea 154 

29.  Artemisia  palmeri 155 

Genus  Chrysothamnus 157 

History,  limits,  and  relationships 157 

Division  into  sections 160 

Origin  and  development  of  sections 161 

Criteria  for  recognition  of  species  and  subspecies. . .  164 

Achene 164 

Pappus 164 

Style-branches 164 

Stamens 165 

Corolla 165 

Number  of  flowers  in  the  head 167 

Involucre 167 

Inflorescence 169 


49413 


PAGE 

Genus  Chrysothamnus — Continued. 

Leaves 169 

Stem  and  bark 169 

Roots 169 

Pubescence 170 

Resins,  oils,  and  other  physiological  products. . .  .  171 

Habit 171 

Fixity    of    species    and    subspecies    and    of    their 

characters 171 

Generic  diagnosis 174 

Key  to  the  sections  and  species  of  Chrysothamnus.  175 

Section  I.     Punctati 175 

1.  Chrysothamnus  paniculatus 175 

Description 175 

Distribution 175 

Relationships 176 

Ecology  and  uses 176 

2.  Chrysothamnus  teretifohus 176 

Section  II.  Typici 178 

3.  Chrysothamnus  gramineus 178 

4.  Chrysothamnus  vaseyi 179 

5.  Chrysothamnus  viscidiflorus 180 

6.  Chrysothamnus  greenei 190 

7.  Chrysothamnus  albidus 192 

Section  III.  Pulchelli 192 

8.  Chrysothamnus  pulchellus 193 

9.  Chrysothamnus  depressus 195 

Section  IV.  Nauseosi 195 

10.  Chrysothamnus  pyramidatus 197 

11.  Chrysothamnus  parryi 198 

12.  Chrysothamnus  nauseosus 209 

Genus  Atriplex 235 

History  and  generic  limits 235 

Origin  and  development  of  sections 237 

Criteria  for  recognition  of  species  and  subspecies. . .  240 

Seed 241 

Flowers 242 

Fruiting  bracts 240 

Inflorescence 243 

Leaves 243 

Pubescence 243 

Habit 243 

Generic  diagnosis 244 

Artificial  key  to  species  of  Atriplex 244 

1.  Atriplex  hortensis 247 

Description 247 

Distribution 247 

Minor  variations  and  synonyms 247 

Relationships 248 

Ecology  and  uses 248 


Genus  Atriplex— 

2.  Atripl 

3.  Atrip 

4.  Atrip 

5.  Atrip 

6.  Atrip 

7.  Atrip 

8.  Atrip 

9.  Atrip: 

10.  Atrip 

11.  Atripl 

12.  Atrip 

13.  Atrip 

14.  Atrip: 

15.  Atrip 

16.  Atrip: 

17.  Atrip: 

18.  Atrip: 

19.  Atrip 

20.  Atrip: 

21.  Atrip: 

22.  Atrip: 

23.  Atrip: 

24.  Atrip 

25.  Atrip 

26.  Atrip: 

27.  Atrip 

28.  Atrip: 

29.  Atrip: 

30.  Atrip 

31.  Atrip 

32.  Atrip 

33.  Atrip 

34.  Atrip 

35.  Atrip 

36.  Atripl 

37.  Atrip 

38.  Atrip 

39.  Atrip 

40.  Atripl 

41.  Atrip 

42.  Atrip 

43.  Atrip 

44.  Atripl 

45.  Atrip 

46.  Atrip 

47.  Atrip 


PAGE 

Contintted. 

iex  patula 248 

lex  cabfornica 257 

ex  maritima 258 

lex  rosea 259 

lex  tatarica 261 

lex  semibaccata 262 

lex  halimoides 263 

ex  dioeca 264 

monilifera 265 

lex  phyllostegia 266 

lex  cordulata 269 

ex  tularensis 271 

expusilla 272 

tenuissima 273 

parishi 274 

ex  truncata 276 

ex  wolfi 279 

ex  gracihflora 279 

ex  saccaria 280 

ex  argentea 282 

ex  coronata 288 

ex  poweUi 290 

ex  leucophyUa 292 

ex  pentandra 294 

ex  elegans 300 

ex  microcarpa 303 

wrighti 304 

bracteosa 305 

ex  linifolia 308 

ex  f ruticulosa 309 

ex  coulteri 310 

decumbens 311 

ex  matamorensis 312 

ex  barclayana 313 

ex  acanthocarpa 320 

ex  obovata 321 

ex  nuttaUi 322 

ex  corrugata 330 

ex  polycarpa 331 

ex  julacea 333 

ex  hymenelytra 333 

ex  lentif ormis 334 

ex  conf ertif olia 338 

ex  spinifera 340 

ex  parryi 341 

ex  canescens 342 


ILLUSTRATIONS. 


1.  Artemisia  abrotanum  and  A.  pontica. 

2.  Artemisia  californica. 

3.  Artemisia  norvegica  heterophylla,  globularia,  glome- 

rata,  and  saxatilis. 

4.  Artemisia  parryi,   A.   senjavinensis,   and   A.   maoro- 

botrys. 

5.  Artemisia  stelleriana  and  A.  alaskana. 

6.  Artemisia  franserioides  and  A.  vulgaris  serrata. 

7.  Artemisia  vulgaris  tilesi  and  typica. 

8.  Artemisia  vulgaris  heterophylla. 

9.  Artemisia  vulgaris  gnaphalodes  and  wrighti,  and  A. 

bigelovi. 

10.  Artemisia  annua,  A.  klotzschiana,  and  A.  biennis. 

11.  Artemisia  absinthium  and  A.  frigida. 

12.  Artemisia  pattersoni  and  A.  scopulorum. 

13.  Artemisia  dracunculus  typica. 

T4.  Artemisia  campestris  typica  and  pacifica. 

15.  Artemisia     campestris     borealis,     spithamaea,     and 

pycnocephala. 

16.  Artemisia  pedatifida  and  A.  filifolia. 

17.  Artemisia  spinescens. 

18.  Artemisia  tridentata  typica  and  parishi. 

19.  Artemisia  tridentata  trifida  and  nova. 

20.  Artemisia  tridentata  arbuscula  and  rothrocki. 

21.  Artemisia  cana. 

22.  Artemisia  rigida  and  A.  pygmaea. 

23.  Artemisia  palmeri. 

24.  Chrysothamnus  paniculatus  and  C.  teretifolius. 

25.  Chrysothamnus  gramineus  and  C.  vaseyi. 

26.  Chrysotliamnus  viscidiflorus  lanceolatus,   puberulus, 

humilis,  elegans,  stenophyllus,  and  pumihs. 

27.  Chrysothamnus  viscidiflorus  linifolius  and  typicus. 

28.  Chrysothamnus  greenei  fiUfolius  and  C.  albidus. 

29.  Chrysothamnus  pulchellus  tjrpicus  and  C.  depressus. 


PLATES 

30. 


Chrysothamnus  pyramidatus  and  C.  parryi  latior. 
Chrysothamnus  parryi  typicus  and  imulus. 
Chrysothamnus  parryi  vulcanicus,  nevadensis,  asper, 

and  howardi. 
Chrysothamnus  nauseosus  speciosus  and  gnaphalodes. 
Chrysothamnus  nauseosus  typicus. 
Chrysothamnus  nauseosus  graveolens. 
Atriplex  hortensis. 
Atriplex  patula  hastata  and  typica. 
Atriplex  rosea,  A.  maritima,  and  A.  tatarica. 
Atriplex  semibaccata,  A.  halimoides,  and  A.  californica. 
Atriplex  phyllostegia,  A.  dioeca,  and  A.  monihfera. 
Atriplex  tularensi.s,  A.  tenuissima,  A.  pusilla,  and  A. 

parishi. 
Atriplex  gracihflora,  A.  wolfi,  and  A.  truncata. 
Atriplex  saccaria,    A.  argentea  typica,   A.  coronata, 

and  A.  cordulata. 
Atriplex  argentea  expansa. 
Atriplex  powelli  and  A.  leucophylla. 
Atriplex  pentandra   arenaria,   muricata,  and  typica, 

and  A.  elegans  typica. 
Atriplex  bracteosa,  A.  wrighti,  and  A.  linifoUa. 
Atriplex  microcarpa,  A.  fruticulosa,  and  A.  coulteri. 
Atriplex  decumbens,  A.  matamorensis,  and  A.  bar- 

clayana. 
Atriplex  obovata  and  A.  acanthocarpa. 
Atriplex  nuttalU  gardneri,  typica,  and  A.  corrugata. 
Atriplex  polycarpa  and  A.  julacea. 
Atriplex  hymenelytra. 
Atriplex  lentiformis  breweri  and  typica. 
Atriplex  lentiformis  griffithsi  and  torreyi. 
Atriplex  oonfertifolia. 
Atriplex  parryi  and  A.  spinifera. 
Atriplex  cauescens  typica,  aptera,  and  linearis. 


TEXT-FIGURES. 


1.  Phylogenetic  chart  of  the  sections  of  Artemisia. 

2.  Achenes  of  Artemisia. 

3.  Leaves  of  Artemisia  vulgaris  heterophylla  to  show 

variation  in  outline. 

4.  Phylogenetic  chart  of  the  species  of  Artemisia,  section 

Abrotanum. 

5.  Inner  bracts  of  Artemisia  norvegica  saxatilis. 

6.  Phylogenetic   chart  of   the  subspecies  of  Artemisia 

norvegica. 

7.  Comparison    of   leaf -outlines   of   Artemisia   vulgaris 

typica  and  heterophylla. 

8.  Portions  of  the  type  specimens  of  Artemisia  vulgaris 

ludoviciana  and  gnaphalodes. 

9.  Phylogenetic   chart   of   the  subspecies   of  Artemisia 

vulgaris. 

10.  Leaves  of  Artemisia  vulgaris  typica  and  tilesi. 

11.  Leaves  of  Artemisia  vulgaris  discolor. 

12.  Variation  in  outline  of  leaves  of  Artemisia  vulgaris 

gnaphalodes. 

13.  Leaves  of  Artemisia  vulgaris  gnaphalodes  and  serrata. 

14.  Phylogenetic  chart  of  the  species  of  Artemisia,  section 

Absinthium. 

15.  Phylogenetic  chart  of  the  species  of  Artemisia,  section 

Dracunculus. 


16.  Phylogenetic   chart   of  the  subspecies   of  Artemisia 

dracunculus. 

17.  Inner  bracts  of  Artemisia  campestris  pacifica. 

18.  Phylogenetic   chart   of   the  subspecies  of  Artemisia 


19.  Phylogenetic  chart  of  the  species  of  Artemisia,  section 

Seriphidium. 

20.  Phylogenetic   chart   of   the  subspecies  of  Artemisia 

tridentata. 

21.  Unusual  leaves  of  Artemisia  tridentata  typica. 

22.  Artemisia  tridentata  trifida  and  bolanderi  and  A.  cana. 

23.  Inner  bracts  of  the  involucre  of  Artemisia  tridentata 

bolanderi  and  A,  cana. 

24.  Leaves  of  Chrysothamnus  teretifolius  and  C.  albidus. 

25.  Phylogenetic   chart   of   the   sections  and   species   of 

Chrysothamnus. 

26.  Phylogenetic  chart  of  subspecies  of  Chrysothamnus 

viscidiflorus. 

27.  Phylogenetic  chart  of  subspecies  of  Chrysothamnus 

parryi. 

28.  Phylogenetic  chart  of  subspecies  of  Chrysothamnus 

nauseosus. 

29.  Phylogenetic  chart  of  subgenera  and  smaller  divisions 

of  Atriplex. 


IV 


ILLUSTRATIONS 


30.  Atriplex  patula  glabriuscula,  litoralis,  and  spicata. 

31.  Atriplex  patula  obtusa  and  alaskensis. 

32.  Variation  of  the  leaves  of  Atriplex  phyllostegia. 

33.  Phylogenetic  chart  of  the  Atriplex  pusilla  group. 

34.  Fruiting  bracts  of  Atriplex  tenuissima. 

35.  Phylogenetic  chart  of  the  Atriplex  truncata  grou]). 
30.  Fruiting  bracts  of  minor  variations  of  Atriplex  argeiitc 

expansa. 

37.  Minor  variations  of  Atriplex  argentea. 

38.  Atriplex  argentea  expansa,  minor  variation  10. 

39.  Phylogenetic  chart  of  the  Atriplex  pcntaiidra  grou]). 

40.  Atriplex  pcntandra  typica. 


41.  Phylogenetic    chart   of    the    sub.species    of    Atriplex 

pentandra. 

42.  Fruiting  bracts  of  Atriplex  elegans. 

43.  Phylogenetic  chart  of  the  shrubby  dioecious  species 

of  Atriplex. 

44.  Phylogenetic    chart    of    the    subspecies    of    Atriplex 

barclayana. 

45.  Leaves  of  Atriplex  nuttalli  buxifolia  and  cuneata. 
4t).  Variation  in  fruiting  bracts  of  Atriplex  nuttalh. 

47.  Phylogenetic    chart    of    the    sul)specie.s    of    Atriplex 
nuttalli. 


THE  PHYLOGENETIC  METHOD  IN  TAXONOMY 


THE  NORTH  AMERICAN  SPECIES  OF  ARTEMISIA, 
CHRYSOTHAMNUS,  AND  ATRIPLEX 


BY 
Harvey  M.  Hall  and  Frederic  E.  Clements 


INTRODUCTION. 

SCOPE  AND  DUTY  OF  TAXONOMY. 

Scope. — The  essence  of  taxonomy  is  clearly  indicated  by  the  meaning  of  the  word 
itself.  It  denotes  the  science  of  arrangement  or  system,  and  hence  classification.  While 
cataloguing  is  a  part  of  it,  it  is  a  small  part  only.  The  naming  of  new  forms  is  a  necessary 
function  of  taxonomy,  but  it  should  always  be  incidental  to  giving  them  their  proper 
meaning  and  relationship,  and  never  an  end  in  itself.  In  the  case  of  plants,  the  mere 
recognition  of  supposed  new  species  in  the  herbarium  hardly  merits  the  term  descriptive 
botany,  and  it  can  in  no  wise  be  regarded  as  adequate  taxonomic  investigation.  It  has  its 
value,  and  hence  its  excuse,  in  the  biological  exploration  of  new  and  distant  countries, 
but,  here  as  elsewhere,  permanent  taxonomic  results  must  await  the  application  of  statis- 
tical and  experimental  methods  in  the  field  (Clements,  1905). 

To  be  both  comprehensive  and  thorough,  taxonomy  must  draw  its  materials  from  all 
other  fields,  just  as  it  must  serve  them  in  turn.  While  it  leans  most  heavily  upon  mor- 
phology, it  can  not  afi'ord  to  neglect  histology  and  physiology,  and  it  must  learn  to  go 
hand  in  hand  with  ecology  and  genetics  in  the  future.  Indeed,  if  it  is  to  reflect  evolution 
as  accurately  as  it  should,  it  must  regard  physiological  adjustment  as  the  basic  pro- 
cess, and  morphological  and  histological  adaptations  as  the  measurable  results.  This 
means  that  the  taxonomist  of  the  future  will  think  in  terms  of  evolutionary  processes, 
and  will  learn  to  treat  his  morphological  criteria  as  dynamic  rather  than  static. 

Relation  to  ecology  and  experimental  evolution. — -As  a  study  of  life  in  its  environment, 
ecology  deals  with  the  motive  force  in  evolution,  and  the  experimental  study  of  evolution 
is  essentially  ecological  in  nature.  Quantitative  ecology  deals  with  the  kind  and  amount 
of  the  stimulus  initial  to  change,  and  Ukewise  measures  the  corresponding  response  in 
terms  of  function  and  structure.  It  thus  traces  the  evolution  of  new  forms  in  minute 
detail,  in  so  far  as  they  arise  through  adaptation  or  variation,  and  consequently  furnishes 
the  only  direct  evidence  of  relationship  by  descent.  It  affords  the  sole  method  of  testing 
the  manifold  assumptions  of  existing  taxonomy,  and  provides  the  foundation  upon  which 
an  objective  and  permanent  taxonomy  may  be  reared.  If  mutations  prove  to  be  but 
major  variations  in  which  the  environic  stimulus  is  hidden  or  indirect,  it  will  become 
possible  to  study  the  origin  of  all  new  features  or  forms  ecologically,  since  hybrids  are 
to  be  regarded  as  new  expressions  of  old  forms.  It  appears  probable  that  this  method 
can  be  successfully  applied  to  retracing  the  origin  of  existing  species  or  stocks,  and  with 
increasing  knowledge  and  skill  in  experimental  manipulation,  to  repeating  the  change 
from  a  genus  into  a  related  one.  Since  tribes  and  families  are  but  related  phyla  of  genera, 
it  seems  not  impossible  to  pass  from  one  family  to  another  experimentally,  especially 
where  the  gap  is  slight,  as  between  Ranunculaceae  and  Rosaceae,  or  Borraginaceae 
and  Verbenaceae.  In  short,  experimental  and  quantitative  methods  promise  to  turn 
taxonomy  from  a  field  overgrown  with  personal  opinions  to  one  in  which  scientific 
proof  is  supreme.  Such  a  taxonomy  is  indispensable  to  the  advance  of  ecology,  and 
apparently  can  be  attained  only  by  adopting  its  methods. 

The  attitude  of  the  ecologist  has  already  been  expressed  by  Clements  (1905:12): 

"Taxonomy  is  distinct  from  descriptive  botany,  which  is  merely  a  cataloguing  of  all  known  forms,  with 
little  regard  to  development  and  relationship.  The  consideration  of  the  latter  is  peculiarly  the  problem  of 
taxonomy,  but  the  solution  must  be  sought  through  experimental  evolution.  The  first  task  of  the  latter  is 
to  determine  the  course  of  modification  in  related  forms,  and  the  relationships  existing  between  them.  With 
this  information,  taxonomy  can  group  forms  according  to  their  rank,  i.e.,  their  descent.  The  same  method  is 
applicable  to  the  species  of  a  genus,  and,  in  a  less  degree,  perhaps,  to  the  genera  which  constitute  a  family. 
The  use  to  which  it  may  be  put  in  indicating  family  relationships  will  depend  largely  upon  the  gap  existing 

3 


4  THE    PHYLOGENETIC   METHOD   IN   TAXONOMY. 

between  the  families  concerned.  While  interpretation  will  always  play  a  part  in  taxonomy,  the  general  use 
of  experiment  wiU  leave  much  less  opportunity  for  the  personal  equation  than  is  at  present  the  case.  Taxonomy, 
like  descriptive  botany,  is  based  upon  the  species,  but,  while  there  may  exist  a  passable  kind  of  descriptive 
botany,  there  can  be  no  real  taxonomy  as  long  as  the  sole  criterion  of  a  species  is  the  difference  which  any 
observer  thinks  he  sees  between  one  plant  and  another.  The  so-called  species  of  to-day  range  in  value  from 
mere  variations  to  true  species  which  are  groups  of  great  constancy  and  definiteness.  The  reasons  for  this 
are  obvious  when  one  recalls  that  'species'  are  still  the  product  of  the  herbarium,  not  of  the  field,  and  that 
the  more  intensive  the  study,  the  greater  the  output  in  'species.'  It  would  seem  that  careful  field  study  of 
a  form  for  several  seasons  would  be  the  first  requisite  for  the  making  of  a  species,  but  it  is  a  precaution  which 
is  entirely  ignored  in  the  vast  majority  of  cases.  The  thought  of  subjecting  forms  presumed  to  be  species 
to  conclusive  test  by  experiment  has  apparently  not  even  occurred  to  descriptive  botanists  as  yet.  Notwith- 
standing, there  can  be  no  serious  doubt  that  the  existing  practice  of  re-splitting  hairs  must  come  to  an  end  sooner 
or  later.  The  remedy  will  come  from  without  through  the  application  of  experimental  methods  in  the  hands 
of  the  ecologist,'  and  the  cataloguing  of  slight  and  unrelated  differences  will  yield  to  an  ordered  taxonomy." 

Duty. — While  the  first  duty  of  taxonomy  is  to  furnish  the  best  possible  record  of 
evolution  and  relationship,  its  next  most  important  task  is  to  be  of  the  greatest  usefulness. 
Fortunately,  there  is  nothing  antagonistic  between  these  two  needs,  for  the  taxonomy 
that  is  based  upon  phylogeny  is  not  only  by  far  the  most  useful,  but  can  also  be  made 
the  most  convenient  and  usable.  For  all  who  deal  with  plants,  and  even  for  the  system- 
atist  outside  his  own  groups,  the  most  usable  taxonomy  is  that  in  which  relationship 
reaches  its  fullest  expression,  both  in  the  forms  recognized  and  the  names  applied. 
This  leads  to  easier  recognition  of  the  plant  and  readier  appUcation  of  its  name,  a  result 
to  which  even  the  speciaUst  can  not  be  indifferent,  unless  he  be  of  the  narrowest  type. 
Even  with  our  present  unsatisfactory  taxonomy,  the  number  of  people  that  make  use  of 
it  has  steadily  increased,  owing  to  the  breaking  down  of  the  artificial  barriers  between 
the  sciences  and  the  rapid  development  of  the  practical  fields  of  agriculture,  grazing, 
and  forestry.  The  time  is  past  when  even  a  morphologist  or  cytologist  can  afford  to 
boast  that  he  does  not  know  a  single  plant  by  name,  while  for  the  geneticist  and  ecologist, 
species  and  variads^  are  the  very  essence  of  their  work.  The  gradual  disappearance  of 
the  unnatural  boundary  between  botany  and  zoology  makes  it  all  the  more  necessary  to 
have  a  kind  of  systematic  botany  that  appeals  to  the  zoologist,  whose  general  use  of  the 
trinomial  indicates  a  greater  feeling  for  relationship.  The  use  of  genera  and  species 
by  the  agronomist,  grazing  expert,  and  forester  is  fundamental,  and  is  limited  only  by 
the  convenience  and  intelligence  of  the  taxonomic  treatment  available.  Even  with 
those  to  whom  plants  are  not  the  immediate  object  of  attack,  such  as  soil  chemists 
and  physicists,  topographers,  geologists,  etc.,  much  more  attention  would  be  given 
vegetation  if  manuals  met  their  needs. 

SCIENTIFIC  BASIS  OF  TAXONOMY. 

Classification  and  relationship. — The  need  of  classifying  plants  has  been  felt  since 
Aristotle  (334  b.  c),  and  the  history  of  classification  is  one  of  attempts  to  achieve  a 
more  natural  system,  except  for  the  artificial  system  of  Linnaeus  (1737).  The  natural 
classification  of  flowering  plants  properly  dates  from  Jussieu  (1789),  since  which  time 
progress  has  been  chiefly  crystalUzed  in  the  systems  proposed  by  DeCandoUe  (1813, 
1819),  EndUcher  (1836),  Lindley  (1845),  Bentham  (1862),  Eichler  (1876),  Luerssen 
(1882),  Engler  (1892),  and  Bessey  (1896).  In  spite  of  its  apparent  simplicity  and  great 
popularity,  the  Linnaean  system  gradually  yielded  to  the  CandoUean  and  Benthamian 
during  the  first  half  of  the  nineteenth  century.  The  spirit  of  development  that  swept 
through  botany  with  the  rise  of  the  cell-theory  and  the  consequent  impetus  to  physiology 
and  morphology  reacted  favorably  upon  taxonomy.     During  the  following  half-century, 

'  By  the  term  ecologist  is  understood  anyone  that  employs  quantitative  and  experimental  methods  in  the  study _of 
plants  or  animals  in  the  natural  habitat. 

>  This  term  is  employed  for  any  form  of  the  species,  as  discussed  on  p.  23. 


INTRODUCTION.  O 

the  many  relicts  of  artificial  systems  were  eliminated  by  Luerssen,  Engler,  and  Bessey, 
and  it  is  perhaps  not  too  much  to  say  that  the  modified  Besseyan  system,  which  has 
drawn  upon  many  others,  is  as  natural  as  the  present  state  of  knowledge  permits.  Such 
systems  have  dealt  chiefly  with  the  relationships  of  orders  and  families,  however,  and 
are  often  very  unsatisfactory  in  their  treatment  of  genera  and  species. 

Relationship  is  the  very  essence  of  classification.  This  axiom  is  universally  accepted 
in  theory,  but  too  often  ignored  in  practice,  especially  by  the  segregator.  It  is  not  suffi- 
cient that  the  relationship  be  felt,  but  it  must  also  be  shown.  This  can  not  be  done  by 
raising  the  sections  of  a  genus  to  generic  rank,  or  the  variads  of  a  species  to  specific 
rank,  and  this  fact  constitutes  the  most  serious  indictment  against  such  practices. 
Moreover,  while  it  is  generally  recognized  that  orders  should  be  arranged  and  famihes 
grouped  in  such  manner  as  to  reveal  their  relationship,  it  is  not  usually  realized  that 
a  similar  relation  should  obtain  between  the  genus  and  its  sections,  and  between  a  species 
and  its  variads.  This  principle  is  later  discussed  in  detail,  and  here  it  will  suffice  to 
point  out  its  basic  importance  for  a  consistently  natural  system. 

Evolution  and  phylogeny. — Evolution  is  the  process  and  phylogeny  the  record  of  descent. 
Phylogeny  is  thus  the  measure  of  relationship,  and  is  to  be  expressed  in  terms  of  com- 
munity of  ancestry;  hence,  if  relationship  is  to  express  evolution  adequately,  it  must 
take  account  of  each  change,  from  the  branch  to  the  variad.  It  must  arrange  these 
in  their  proper  phylogenetic  order,  and  denote  them  by  such  terms  as  will  clearly  indicate 
their  fixed  phylogenetic  position.  This  has  long  been  done  for  the  most  part,  but  the 
fact  has  too  often  been  overlooked  that  the  sequence  of  changes  is  fixed  in  practically 
all  regions  of  intense  evolution.  The  genus  exhibits  lines  of  evolution  expressed  in 
the  sections,  and  the  species  shows  more  recent  changes  marked  by  variads.  It  serves 
no  useful  purpose,  but  merely  obscures  evolution  and  phylogeny  to  treat  the  sections  of 
Astragalus,  Gentiana,  or  Pinus  as  though  they  were  genera,  or  the  numerous  variads  of 
Artemisia  vulgaris  or  Chrysothamnus  nauseosus  as  species.  A  natural  classification 
must  maintain  as  well  as  reveal  the  different  degrees  of  relationship  'as  expressions  of 
different  stages  of  evolution,  and  it  can  do  this  most  accurately  with  genera,  sections, 
species,  and  variads,  where  the  lines  of  evolution  are  still  in  a  condition  conducive  to 
experimental  study. 

The  evidences  of  evolution  are  the  materials  of  phylogeny,  and  these  have  been  almost 
exclusively  morphological  up  to  the  present.  Experimental  studies,  such  as  those  of 
Bonnier  (1895,  1920),  Jordan  (1873),  and  the  geneticists,  have  been  few,  and  for  the 
most  part  without  taxonomic  objectives.  Such  work  serves  to  prove  that,  while  it  is 
convenient  to  employ  morphological  observations,  it  is  neither  necessary  nor  desirable 
to  do  so  without  supplementing  and  checking  them  by  means  of  statistical  and  experi- 
mental methods.  Since  the  limits  of  orders  and  families  are  determined  by  genera,  and 
the  limits  of  genera  by  species,  the  whole  problem  resolves  itself  into  a  statistical  and 
experimental  study  of  species  and  their  evolution.  Pending  the  general  adoption  of 
such  methods,  morphology  will  continue  to  be  employed,  but  it  should  be  with  due  recog- 
nition of  the  fact  that  both  criteria  and  results  are  tentative  and  must  be  confirmed  by 
objective  methods.  While  paleontology  has  often  made  brilliant  use  of  morphology  in 
connection  with  sequence  in  tracing  the  course  of  evolution,  its  criteria  for  genera  and 
species  have  necessarily  been  drawn  from  existing  units,  and  are  similarly  susceptible 
to  refinement  as  a  consequence  of  statistical  and  experimental  studies. 

Synthesis  and  analysis. — The  prevailing  practice  in  the  segregation  of  genera  and 
species  is  chiefly  detached  analysis,  with  little  consideration  of  relationship  and  prac- 
tically none  of  evolution.  Superficially,  this  practice  would  seem  to  follow  the  course 
of  evolution,  since  the  latter  is  primarily  a  matter  of  differentiation.  As  a  matter  of 
fact  this  is  usually  expressed  in  a  vast  number  of  individuals  scattered  over  a  wide 


6  THE    PHYLOGENETIC   METHOD    IN   TAXONOMY. 

territory  and  growing  in  a  considerable  range  of  differences  within  the  habitat,  or  often 
in  different  habitats.  An  analysis  based  upon  a  few  herbarium  specimens  or  frequently 
indeed  upon  a  single  one  can  rarely  be  more  than  a  personal  opinion  and  usually  affords 
but  an  erroneous  or  imperfect  impression  of  the  actual  species.  With  reference  to  the 
evidence  provided  by  Nature,  then,  the  synthesis  of  data  from  various  regions  is  imper- 
ative if  a  complete  and  exact  picture  of  the  species  is  to  be  obtained.  The  statistical 
method  itself,  while  it  is  analytic  in  that  it  deals  with  individuals,  is  synthetic  in  as 
much  as  it  relates  the  individuals  studied  to  the  mode  for  the  locality  as  well  as  for  the 
species.  The  experimental  method  appears  to  be  intrinsically  analytic,  since  it  deals 
with  the  differentiation  of  the  stock.  However,  its  most  successful  use  so  far  in  the 
field  has  been  to  relate  ecads  to  the  parent  stock  and  the  so-called  reciprocals  to  each 
other  (Clements  and  Hall,  1922).  Moreover,  in  working  with  the  differentiation  of  a 
stock  in  various  habitats,  the  synthetic  factor  is  given  full  value  at  the  outset,  and  the 
task  is  then  merely  one  of  analyzing  the  evolutionary  possibilities  of  the  species.  Finally, 
the  examination  of  any  group  of  individuals  produced  experimentally  involves  the  deter- 
mination of  the  mode  of  the  departure  as  well  as  the  extremes.  Thus,  in  building  a 
natural  system,  synthesis  and  analysis  must  go  hand  in  hand;  it  is  the  task  of  analysis 
to  find  new  facts  and  of  synthesis  to  give  them  their  proper  meaning. 

THE  GENUS  CONCEPT. 

Nature  of  the  genus. — In  the  prevalent  view  the  genus  appears  to  be  regarded  merely 
as  a  concept,  and  it  is  often  stated  that  it  does  not  actually  exist  in  nature.  This  is 
doubtless  true  for  those  who  regard  the  genus  merely  as  a  pigeon-hole,  chiefly  convenient 
for  the  filing  of  new  species.  Such  a  view  has  its  justification  in  the  usual  practice 
of  making  genera,  and  especially  in  the  recent  flood  of  generic  segregation^  It  is  not 
supported  by  the  evidence  drawn  from  the  methods  of  evolution  or  the  record  of  phy- 
logeny.  To  the  student  of  evolution,  the  genus  represents  a  certain  characteristic  portion 
of  the  line  or  field  of  specialization,  and  its  existence  is  as  definite  as  that  of  the  species 
which  constitute  it.  It  may  be  more  difficult  to  recognize,  but  this  is  primarily  the 
fault  of  outlook  and  method.  In  the  absence  of  definite  criteria,  the  chief  difficulty 
centers  about  the  rank  and  limits  of  genera.  As  a  consequence  of  the  unrestricted 
play  of  personal  opinion,  not  infrequently  aided  by  bias  or  carelessness,  present-day 
taxonomy  contains  genera  of  every  possible  quality.  Many  of  these  disappear  com- 
pletely when  the  test  of  evolution  is  applied  to  them.  Given  the  family,  genus,  and 
species  as  major  units,  these  will  regularly  be  differentiated  into  tribes,  sections,  and 
variads,  respectively.  This  is  a  necessary  corollary  of  the  principle  that  the  processes 
of  evolution  are  constantly  and  universally  at  work.  The  basic  laws  of  conservation 
of  energy  and  material,  division  of  labor,  and  increase  of  parental  care  lead  inevitably 
to  divergence,  and  hence  to  the  splitting  of  the  generic  stock  into  sections,  and  of  the 
specific  stock  into  variads. 

The  question  of  generic  limits  is  one  of  criteria.  These  have  been  of  the  most  various 
kinds  and  quality,  and  have  led  to  results  of  the  most  diverse  value.  It  seems  obvious 
that  personal  opinion  is  the  poorest  of  bases  for  determining  the  relative  merits  of  criteria, 
and  that  improvement  in  this  respect  can  be  effected  only  by  means  of  experimental 
and  statistical  studies  of  the  generic  criteria  in  use.  Until  this  is  done,  the  segregation 
of  well-established  genera  can  have  no  standing  in  evolutionary  taxonomy. 

Genus  and  section. — The  relation  of  the  subgenus  or  section  to  the  genus  is  a  basic 
and  natural  one,  arising  out  of  evolution  and  serving  as  a  record  of  it.  It  was  inevitable 
that  genera  of  wide  extent  in  contact  with  many  effective  habitats,  such  as  circum- 
polar  ones,  should  show  wide  differentiation.  The  generic  stock  became  split  up  into 
several  or  many  lines  of  evolution,  each  with  its  secondary  development.    So  funda- 


INTRODUCTION.  7 

mental  and  uniform  was  this  process  that  its  consequences  are  to  be  found  in  practically- 
all  genera  that  have  attained  considerable  differentiation  of  species.  It  corresponds 
to  the  basic  law  of  adaptation  and  speciaUzation  under  the  pressure  of  new  conditions, 
and  the  maintenance  of  their  evolutionary  relationship  is  the  chief  task  in  the  groups 
thus  produced.  The  differentiation  of  the  sections  is  subsequent  and  subordinate  to 
that  of  the  genus,  and  any  treatment  that  ignores  or  obscures  this  fact  is  as  undesirable 
as  it  is  unnatural.  To  all  who  recognize  that  taxonomy  should  be  the  best  possible 
interpretation  of  evolution,  the  confusion  of  genera  and  subgenera  appears  to  negative 
all  the  principles  upon  which  evolutionary  taxonomy  should  rest. 

Generic  segregation. — The  general  tendency,  during  the  last  two  decades  in  America 
at  least,  has  been  to  segregate  genera  by  raising  their  sections  to  generic  rank.  While 
the  practice  is  not  confined  to  this  period,  it  is  characteristic  of  it.  Not  all  large  genera 
have  received  this  treatment  as  yet,  but  another  decade  or  two  will  see  this  done,  unless 
it  is  given  a  sharp  check  by  the  scientists  who  suffer  from  it.  This  tendency  to  assign 
generic  rank  to  smaller  and  smaller  divisions  is  the  natural  result  of  studies  by  specialists, 
who  often  focus  their  attention  upon  details  to  an  extent  that  magnifies  them  out  of 
all  proportion  to  their  value.  Relationship  and  perspective  are  lost,  and  the  results 
are  both  unnatural  and  unusable.  It  is  necessarily  in  the  largest  and  best-known 
genera  that  segregation  has  been  rife,  and  it  is  these  that  offer  the  greatest  opportunity 
for  damage,  both  to  phylogeny  and  to  classification.  In  North  America,  Astragalus 
is  unique  in  that  it  is  now  represented  by  19  genera,  socalled;  Aster  is  segregated  into  13, 
Haplopappus  into  11,  and  Gilia,  Oenothera,  and  Saxifraga  are  broken  up  into  10  or 
more  each.  Habenaria  and  Polygonum  are  each  split  into  6  parts,  Claytonia,  Euphorbia, 
Lotus,  and  Ranunculus  into  5,  and  a  large  number  of  genera  into  4  and  3. 

While  no  complete  presentation  of  the  arguments  for  segregation  seems  to  be  available, 
the  major  reasons  may  be  gained  from  various  sources.  It  is  contended  that  many 
genera,  including  those  mentioned  above,  are  unnatural  groups  of  species  of  diverse 
habit  and  structure,  and  that  they  should  be  split  into  smaller  and  more  natural  ones. 
A  second  argument  is  that  genera  should  be  uniform,  and  that  the  criteria  used  in  certain 
groups  should  be  applied  throughout.  This  is  akin  to  the  contention  that  many  small 
genera  are  more  convenient  than  a  few  large  ones,  and  that  a  genus  should  be  auto- 
matically spUt  up  when  the  species  reach  a  certain  number.  Finally,  it  is  sometimes 
maintained  that  justice  to  obscure  workers  demands  that  their  genera  should  be  adopted, 
since  they  are  as  good  as  many  of  those  already  in  use. 

Failures  of  segregation. — The  most  conspicuous  failure  of  the  method  of  generic 
segregation  is  in  connection  with  phylogeny  and  classification.  The  18  segregates  of 
Astragalus  are  much  more  nearly  related  to  each  other  than  they  are  to  Robinia  or 
Trifolium,  but  there  is  no  evidence  of  this  fact  in  their  treatment.  The  only  possible 
phylogenetic  and  taxonomic  treatment  of  these  is  to  include  them  in  Astragalus  as 
sections,  differentiated  more  or  less  recently  from  the  same  generic  stock.  This  is  like- 
wise the  answer  to  the  contention  that  Astragalus,  Aster,  Gilia,  Gentiana,  Oenothera,  etc., 
are  unnatural  groups,  and  that  they  are  rendered  more  natural  by  raising  their  sections 
to  generic  rank.  If  further  answer  is  sought,  it  may  be  obtained  by  trying  to  locate 
an  Astragalus  in  the  18  segregates  that  represent  its  sections.  The  endeavor  to  give 
criteria  the  same  value  throughout  and  to  make  genera  uniform  fails  because  evolution 
is  far  from  uniform,  and  its  products  share  this  quality.  Moreover,  it  is  significant 
that  practically  all  such  attempts  confine  themselves  to  reducing  genera  to  the  rank 
of  the  least  valid,  instead  of  combining  the  less  natural  genera  to  increase  their  validity 
in  terms  of  evolution  and  relationship. 

The  assumption  that  many  small  genera  are  more  convenient  than  fewer  large  ones 
shows  a  curious  ignorance  of  the  significance  of  system,  and  of  the  mechanism  of  memory. 


8  THE    PHYLOGENETIC    METHOD    IN   TAXONOMY. 

It  is  the  essence  of  a  system  to  organize  knowledge,  and  the  conversion  of  generic  sec- 
tions into  genera  conceals  their  inherent  relationship.  The  most  striking  feature  of 
memory  is  its  necessity  for  relating  things  to  each  other,  and  the  multiplication  of 
small  genera  without  evident  relationship  to  each  other  greatly  increases  the  labor 
involved  in  remembering  them,  often  to  the  degree  that  the  worker  can  not  or  will  not 
utilize  them.  The  argument  that  generic  segregates  should  be  adopted  in  justice  to 
the  authors  concerned,  since  they  are  quite  as  good  as  some  accepted  genera,  is  possible 
only  because  of  the  failure  to  realize  that  synthesis  and  not  analysis  is  the  corner-stone 
of  classification.  The  question  of  justice  is  entirely  subordinate  to  the  demands  of 
evolution  and  phylogeny,  and  it  is  certain  that  these  can  not  be  met  by  segregation 
of  the  usual  sort. 

It  is  clearly  recognized  that  the  making  of  new  genera  is  purely  a  matter  of  personal 
judgment  at  the  present  time,  and  that  this  is  profoundly  affected  by  training  and 
environment,  and  especially  by  prejudices  in  favor  of  uniformity,  segregation,  etc. 
There  is  no  general  agreement  as  to  criteria,  methods,  or  results,  and  the  importance 
of  evolution  as  the  one  safe  guide  is  rarely  if  ever  considered.  A  knowledge  of  the  genus 
as  a  whole,  especially  when  it  includes  exotic  species,  is  too  often  lacking,  and  little  or 
no  thought  is  given  to  the  phylogeny  of  the  genus  and  its  sections  in  relation  to  genera 
of  the  same  evolutionary  stock.  More  serious  still  is  the  all  but  inevitable  magnifying 
of  criteria  in  the  detached  herbarium  study  of  a  group  or  genus  and  the  consequent 
lowering  of  the  criteria  for  genera.  The  first  cycle  of  this  sort  is  nearing  a  close  for  lack 
of  material  for  segregation,  and  it  is  confidently  to  be  expected  that  the  next  generation 
will  see  a  new  lowering  of  criteria  and  a  corresponding  avalanche  of  segregates.  This 
can  be  avoided  only  by  a  stern  insistence  on  the  part  of  conservative  taxonomists, 
and-  of  all  non-taxonomists,  that  changes  in  generic  concepts  must  be  based  upon  evolu- 
tion, and  made  only  after  the  fullest  statistical  and  experimental  studies.  An  augury 
of  the  future  of  descriptive  botany  is  furnished  by  the  case  of  Astragalus,  in  which 
Homalobus,  one  of  the  18  segregates,  already  has  almost  as  many  so-called  species  as 
the  ecological  treatment  recognizes  for  the  entire  genus  in  North  America. 

With  respect  to  usability,  the  segregation  of  genera  is  especially  unfortunate.  It  is 
impossible  for  most  botanists  and  practically  all  laymen  to  determine  a  large  number 
of  the  generic  segregates  without  recourse  to  the  herbarium,  and  their  recognition  in 
the  field  is  practically  out  of  the  question  for  all  but  the  specialists  in  the  group  concerned. 
Ready  recognition  means  carrying  the  distinctive  criteria  in  mind,  and  only  the  specialist 
can  hope  to  know  the  names  of  the  segregates,  to  say  nothing  of  their  characters.  More- 
over, there  is  a  definite  limit  to  the  number  of  names  the  taxonomist  himself  can  readily 
command,  and  this  Umit  is  quickly  reached  with  the  great  majority  of  those  who  use 
taxonomy  merely  as  a  tool.  If  the  actual  genera  of  the  pea  family  are  to  be  known 
and  recognized  on  sight,  it  becomes  a  mental  impossibility  to  deal  with  Astragalus  when 
split  into  19  parts.  When  the  same  process  is  carried  into  scores  of  genera,  a  working 
knowledge  of  flowering  plants  becomes  impossible  for  anyone  but  the  taxonomist,  and 
it  is  possible  for  him  only  in  the  restricted  groups  with  which  he  is  working.  As  a  con- 
sequence, taxonomy  becomes  an  object  of  ridicule  to  those  who  would  use  it  and  can 
not,  and  this  feeling  is  extended  to  the  whole  subject  of  botany  by  the  layman,  who 
properly  looks  upon  the  naming  of  plants  as  the  first  step  in  botanical  knowledge. 

Proper  treatment  of  genera. — It  has  repeatedly  been  emphasized  that  the  treatment 
of  genera  must  be  based  upon  evolution  and  phylogeny.  This  means  the  retention 
of  the  vast  majority  of  genera  as  recognized  by  Linnaeus,  Bentham,  Gray,  and  others, 
together  with  the  recognition  of  the  subgenus  or  section  as  an  essential  unit  for  recording 
the  course  of  evolution.  From  the  evolutionary  standpoint,  this  requires  the  replacing 
of  generic  segregates  in  their  original  genera,  except  in  the  rare  cases  where  the  genus 


INTRODUCTION.  « 

is  plainly  an  artificial  one.  Since  there  is  no  intent  to  minimize  analysis  when  it  is  in 
agreement  with  evolution,  it  would  seem  desirable  to  make  rather  more  of  sections  as 
records  of  recent  lines  of  specialization  within  the  generic  stock.  This  can  readily  be 
done  by  making  them  more  prominent  in  the  treatment  of  genera,  and  in  special  cases 
by  the  use  of  the  sectional  name  or  initial  in  a  trinomial.  With  respect  to  practica- 
bility, the  use  of  genus  and  section  alone  makes  possible  the  correlations  that  are  essential 
to  a  working  knowledge  of  taxonomy.  This  likewise  insures  the  smallest  possible  number 
of  genera,  which  is  also  a  cardinal  point  in  usability.  Moreover,  this  method  permits 
the  accumulation  of  a  permanent  body  of  knowledge,  both  for  the  subject  and  the 
individual,  as  the  constitution  of  each  genus  is  no  longer  subject  to  the  personal  judg- 
ment of  every  specialist.  This  is  especially  significant,  in  view  of  the  fact  that  the  raising 
of  actual  sections  to  genera  does  not  represent  new  knowledge,  but  rather  an  ignoring 
of  the  essential  facts  of  relationship.  When  the  latter  are  given  their  full  value,  there 
will  be  no  question  as  to  the  usability,  convenience,  and  attractiveness  of  taxonomy 
for  all  those  who  wish  to  make  use  of  it. 

THE  SPECIES  CONCEPT. 

Nature  of  the  species.— As  with  the  genus,  there  has  been  much  divergence  of  views 
as  to  whether  the  species  is  merely  a  concept  or  an  actual  entity.  Apparently,  the 
general  opinion  is  to  the  effect  that  the  species  is  a  concept,  but  this  seems  to  deal  with 
the  term  and  its  application  rather  than  with  the  unit  itself.  Once  granted  that  the 
term  might  have  been  applied  to  any  other  unit,  or  an  altogether  different  term  employed, 
it  seems  evident  that  the  unit  itself  is  as  definite  an  entity  as  a  plant  community. 
In  fact,  with  many  dominants  and  subdominants,  the  species  and  the  community  are 
coextensive,  and  hence  equally  definite.  Like  the  genus,  the  species  represents  a  certain 
portion  of  the  line  of  evolution,  and  it  lacks  definiteness  only  where  evolution  has 
progressed  uniformly,  without  sharp  divergences  or  breaks.  Practically  all  species  are 
still  susceptible  of  modification,  and  many  of  them  exhibit  it  most  actively.  If  only 
the  end  results  of  this  process  are  known,  as  in  the  case  of  herbarium  studies,  they  appear 
to  be  distinct  units,  often  with  little  or  no  evidence  of  their  common  origin.  As  a  con- 
sequence, units  of  every  possible  degree  of  differentiation  and  value  are  masquerading 
as  species  in  existing  taxonomy.  As  long  as  species  are  made  in  the  herbarium  instead 
of  the  field,  this  condition  must  continue,  at  least  in  some  degree,  but  it  will  disappear 
rapidly  before  statistical  and  experimental  studies  in  the  natural  habitats.  Such  studies 
have  already  reached  the  point  where  it  is  possible  to  relate  a  number  of  recent  segre- 
gates to  their  proper  specific  stock,  and  they  indicate  that  this  will  be  the  regular  out- 
come of  such  methods. 

Definition  of  species. — Many  attempts  have  been  made  to  provide  a  working  definition 
of  the  term  species,  but  these  have  been  successful  only  in  leading  to  widely  divergent 
usages.  The  old  definition  based  upon  sterility  has  long  been  discarded,  but  its  place 
has  been  taken  in  some  measure  by  the  definition  of  the  geneticists,  which  is  based 
upon  gametic  purity.  This  basis  has  actually  been  proposed  by  Lotsy  (1916),  and  it 
does  have  the  advantage  of  being  more  objective  than  any  other.  It  is  a  concept  of 
use  to  geneticists  alone,  however,  since  gametic  purity  can  only  be  determined  by  genetic 
analysis,  and  this  is  applicable  so  far  to  relatively  few  cases.  Plants  entirely  identical 
in  all  external  characters  may  exhibit  a  different  gametic  composition,  as  indicated  by 
their  behavior  when  hybridized,  and  would  accordingly  constitute  different  species. 
The  classical  example  of  this  are  the  two  strains  of  white  sweet  peas  described  by  Bateson 
(1913),  and  a  similar  case  is  found  in  the  14  strains  of  corn,  all  with  white  aluerone 
(Babcock  and  Clausen,  1918).     It  is  obvious  that  such  a  definition  of  the  species  is 


10  THE    PHYLOGENETIC   METHOD    IN   TAXONOMY. 

wholly  impracticable,  and  that  genetic  analysis  can  be  of  value  taxonomically  only 
in  studying  differentiation  within  the  species  itself. 

Constancy. — A  more  generally  accepted  basis  for  the  species  is  its  constancy,  or  the 
ability  to  "breed  true."  While  it  is  doubtless  true  that  practically  all  actual  species 
do  this,  many  of  the  segregates  of  to-day  do  not.  More  significant  still  is  the  fact  that 
the  adherents  of  this  definition  make  no  attempt  to  determine  this  point  before  describing 
a  new  species.  Constancy  is  undoubtedly  a  factor  to  be  regularly  taken  into  account 
in  the  evolutionary  study  of  species,  but  it  is  futile  to  attempt  this  without  the  aid  of 
statistical  and  experimental  methods.  On  the  other  hand,  the  test  of  constancy  alone 
would  require  the  acceptance  of  an  absurd  number  of  species.  For  example,  Jordan 
(1873)  recognized  200  species  of  Draba  verna,  the  "Jordanons"  of  Lotsy  (1916),  and  the 
United  States  Department  of  Agriculture  recognizes  250  varieties  of  wheat,  all  of  which 
breed  true  and  would  thus  come  to  be  species.  But  these  are  based  upon  characters 
that  taxonomers  regard  as  slight  and  non-specific.  The  case  of  Draba  verna  shows  that 
this  condition  is  not  confined  to  cultivated  plants,  and  this  is  borne  out  by  studies  of 
Cerastium  viscosum,  Montia  perfoliata,  and  other  species  at  the  University  of  California. 

Extensive  field  studies  in  connection  with  the  present  monograph  have  revealed 
innumerable  examples  of  very  similar  forms  that  evidently  breed  true.  The  acceptance 
of  this  criterion  would  increase  the  number  of  species  almost  beyond  belief,  and  it  would 
throw  taxonomy  into  inextricable  confusion.  The  idea  of  constancy  is  helpful  in  dis- 
tinguishing between  fixed  genetic  units  and  ecads,  and  is  one  of  the  first  points  to  be 
considered  in  the  experimental  analysis  of  a  specific  stock.  It  already  appears  probable, 
however,  that  the  prevalent  opinion  that  forms  are  constant  or  not  constant  will  have 
to  be  modified,  and  that  varying  degrees  of  constancy  must  be  recognized. 

Distinctness. — Regardless  of  the  fetish  of  constancy,  the  working  definition  of  the 
average  taxonomist  is  distinctness,  by  which  he  understands  the  ready  recognition  of 
a  particular  form.  It  may  easily  be  shown  that  distinctness  or  recognizability  in  itself 
is  no  necessary  test  of  a  species.  Nothing  is  more  readily  recognized  than  the  albino 
mutants  of  blue  and  purple  flowers,  but  even  the  most  extreme  segregator  rarely  proposes 
to  call  them  species.  Moreover,  recognizability  is  too  often  a  matter  of  the  herbarium, 
and  completely  disappears  in  the  field,  or  the  limits,  of  the  unit  fade  away.  It  is  pecu- 
liarly the  faculty  of  the  specialist,  who  sees  the  finest  details  in  bold  relief,  and  it 
frequently  vanishes  with  adequate  perspective.  It  ignores  the  various  degrees  of 
differentiation,  and  emphasizes  apparent  values  at  the  expense  of  the  real  ones.  More- 
over, this  working  test  is  applied  without  any  real  attempt  at  consistency,  since  ecads 
are  not  regarded  as  species  when  their  origin  is  known,  but  are  called  ecologic  forms,  in 
spite  of  the  fact  that  a  large  number  of  the  specific  segregates  of  to-day  are  ecads,  which 
are  not  generally  recognized  as  such  because  they  are  known  only  in  the  herbarium. 

The  idea  that  recognizability  was  a  test  of  the  species  was  probably  in  the  mind  of 
Bateson,  when  he  gave  systematists  the  interesting  advice  to  describe  all  the  species 
that  they  could  induce  any  reputable  journal  to  print  (1913^).  This  advice  is  so  unsound 
as  to  bring  its  own  condemnation,  but  it  is  useful  in  revealing  the  complete  lack  of 
understanding  of  the  foundations  of  taxonomy.  While  it  must  be  confessed  that  too 
much  practice  excuses  the  view  that  taxonomy  is  merely  a  matter  of  new  species  and 
many  of  them,  no  one  who  regards  science  as  organized  knowledge  can  fail  to  see  that 
taxonomy  has  no  real  standing  apart  from  evolution.  To  follow  Bateson's  advice  would 
add  enormously  to  the  already  jmmense  accumulation  of  so-called  species,  the  origin 
and  relationship  of  which  no  one  understands.  What  is  now  needed  is  not  the  further 
increase  of  such  segregates,  easy  to  discover  and  describe  by  the  thousand,  but  the 
organization  of  this  chaotic  mass  into  natural  groups.  The  method  of  the  segregator 
is  to  take  the  scattered  and  broken  twigs  of  the  evolutionary  tree  and  catalogue  them 


INTRODUCTION.  11 

without  concern  as  to  their  origin  and  relationship,  while  the  true  method  of  taxonomy 
is  to  deal  with  the  tree  as  a  whole,  and  to  regard  the  units  in  it  as  so  much  correlated 
evidence  of  evolution. 

The  evolutionary  definition. — To  the  student  of  evolution,  all  these  proposed  tests  of 
species  are  gratuitous,  arising  from  an,  incomplete  view  of  the  field  and  suffering  from 
the  bias  of  the  specialist.  While  gametic  purity,  constancy,  and  recognizability  all  have 
their  meaning,  this  is  as  yet  too  little  understood  to  make  them  little  more  than  inter- 
esting working  hypotheses.  There  is  no  warrant  in  our  present  knowledge  of  the  course 
of  evolution  for  assuming  that  they  have  any  more  connection  with  the  species  than 
with  the  most  recent  ecad  or  mutant.  The  evolutionary  view  of  the  species  is  that  it 
is  a  definite  phylogenetic  stock,  sprung  from  and  related  to  similar  stocks,  and  itself 
undergoing  modification  into  a  number  of  variads.  As  they  have  recently  come  from 
the  same  stock,  these  variads  are  more  nearly  related  to  each  other  than  they  are  to  those 
of  any  other  species,  and  they  represent  a  definite  phylogenetic  unit,  the  species,  at  the 
same  time  that  they  mark  its  further  differentiation.  The  only  definite  measure  of  the 
progress  of  evolution  is  found  in  the  degree  of  morphological  difference,  and  species 
necessarily  share  this  morphological  basis  with  other  units.  To  ask  that  all  species  show 
the  same  degree  of  morphological  difference  is  to  misunderstand  the  nature  of  evolu- 
tion, but  it  is  possible  to  demand  that  the  great  majority  of  them  show  a  definite  dif- 
ference in  the  proper  position  in  the  sequence  of  units.  In  short,  a  species  must  not 
only  show  adequate  morphological  differentiation,  but  this  must  bear  a  definite  relation 
to  that  of  the  genus  on  the  one  hand  and  of  the  variads  on  the  other.  It  seems  a  truism 
to  point  out  that  in  an  evolutionary  taxonomy  each  unit  must  be  determined  as  much 
or  more  by  its  relation  to  the  unit  that  precedes  and  the  one  that  follows  as  by  its  purely 
structural  characters. 

The  inadequacy  of  a  strict  morphological  basis  for  species  is  due  chiefly  to  the  para- 
mount role  of  divergence.  If  two  species  have  been  differentiated  from  an  original  stock 
by  the  impact  of  reciprocal  factors,  such  as  greater  wetness  on  the  one  hand  and  dryness 
on  the  other,  this  very  divergence  will  give  opportunity  for  convergence  when  they 
invade  reverse  habitats.  This  convergence  may  sometimes  become  practical  identity 
(Clements,  1904),  but  as  a  rule  ancestral  or  related  characters  will  furnish  the  clue  to 
descent.  Thus,  while  most  species  will  show  distinct  gaps,  it  must  be  admitted  that  the 
gap  may  be  quite  or  completely  closed  in  some  instances,  in  which  evolutionary  analysis 
is  alone  of  avail.  In  this  task  ecology  is  often  of  great  assistance  in  relating  response  to 
habitat  and  in  connecting  differentiating  habitats  with  the  habitat  of  the  ancestral 
mass.  Thus,  while  evolutionary  taxonomy  does  not  pretend  to  offer  a  definition  of  the 
species,  it  does  provide  the  method  by  which  species  can  be  recognized  and  by  which 
they  can  be  related  to  each  other  as  well  as  to  the  major  and  minor  units.  The  conse- 
quences of  various  attitudes  toward  the  species  are  discussed  in  the  two  following 
sections,  and  the  details  of  the  evolutionary  method  are  dealt  with  in  the  last  section, 
as  well  as  under  the  later  caption  "Methods  and  results  in  evolutionary  taxonomy." 

The  segregation  of  species. — The  method  of  segregation  that  has  characterized  descrip- 
tive botany  in  America  during  the  past  quarter  of  a  century  is  a  necessary  consequence  of 
the  idea  that  everything  distinguishable  is  a  species.  AppUed  in  the  field,  this  definition 
would  have  worked  little  damage,  as  the  abundance  of  material  would  quickly  have  set 
a  limit  to  its  operation.  In  the  herbarium,  however,  the  small  number  of  individuals 
represented  and  the  frequently  incomplete  nature  of  the  specimens  magnified  small 
differences  and  gave  the  impression  of  gaps  where  none  actually  existed.  In  spite  of 
the  assumption  of  many  descriptive  botanists  that  much  of  their  work  is  done  in  the 
field,  this  rarely  amounts  to  little  more  than  collecting  a  few  individuals  of  the  out- 
standing forms,  and  the  describing  is  wholly  a  matter  of  the  herbarium.    Collecting  for 


12  THE  PHYLOGENETIC  METHOD  IN  TAXONOMY. 

a  complete  range  of  individual  and  specific  variation,  with  thoroughgoing  ecological 
analysis  and  statistical  studies  of  the  amount  and  direction  of  variation,  is  practically- 
unknown.  The  usual  practice  has  had  its  justification  in  the  past,  when  actual  species 
were  still  to  be  described,  as  shown  by  the  results  of  Pursh,  Nuttall,  Torrey,  Gray,  and 
others,  and  these  reasons  still  obtain  in  lands  little  known  botanically,  especially  the 
tropics.  For  North  America,  however,  the  great  majority  of  real  species  had  been 
described  by  the  close  of  Gray's  work,  and  the  vast  increase  of  species  since  that  time 
chiefly  represents  a  change  of  personal  views  as  to  the  criteria  that  mark  this  unit. 

While  there  has  been  an  unfortunate  shifting  of  standards  in  descriptive  botany 
generally,  as  shown  by  the  almost  universal  raising  of  varieties  to  species  (table  1), 
much  of  the  existing  confusion  is  due  to  the  lack  of  sympathy  and  understanding  shown 
by  botanists  toward  the  trinomial.  It  is  probable  that  many  segregators  recognize  that 
most  of  their  new  forms  are  not  actual  species  at  all,  but  the  prevailing  botanical  atti- 
tude toward  trinomials,  and  the  failure  of  at  least  one  code  to  give  varietal  names 
nomenclatorial  standing,  have  discouraged  thinking  in  relationships,  since  this  demanded 
the  use  of  the  trinomial.  The  inconvenience  of  the  latter  is  much  more  than  ofi'set  by 
its  value  in  relating  forms  to  the  specific  stock,  as  is  proven  by  the  practice  of  mam- 
malogists  and  ornithologists  in  particular.  However,  while  it  is  quite  possible  that 
descriptive  botanists  have  felt  some  compulsion  toward  the  apparent  simplicity  and 
uniformity  of  the  binomial,  it  seems  certain  that  the  general  botanist  would  have  found 
no  more  inconvenience  in  the  use  of  trinomials  than  the  zoologist,  had  he  been  given 
the  opportunity. 

Failures  of  specific  segregation. — The  segregation  of  species  has  practically  all  the 
disadvantages  of  generic  segregation,  and  in  addition  some  that  are  peculiar  to  it.  Sub- 
jectively, it  suffers  critically  from  the  inevitable  lack  of  proper  and  adequate  material, 
owing  to  its  being  confined  to  the  herbarium.  Even  more  serious  is  the  fact  that  segre- 
gation is  merely  a  matter  of  personal  judgment,  and  makes  use  of  none  of  the  objective 
checks,  such  as  statistics  and  experiment.  As  already  indicated,  there  is  a  successive 
shifting  of  the  standards  for  criteria,  with  the  result  that  these  always  become  lower  in 
quantitative  terms,  and  never  higher.  Not  only  do  the  standards  differ  from  indivi- 
dual to  individual,  but  sometimes  they  also  change  rapidly  in  the  case  of  the  same 
individual.  This  is  unavoidable  as  long  as  personal  judgment  is  the  only  process  involved, 
and  the  continuance  of  this  as  the  sole  test  will  complete  the  existing  chaos  in  another 
decade. 

From  the  standpoint  of  one  who  must  make  use  of  the  results,  the  greatest  harm  done 
by  segregation  arises  from  its  treatment  of  all  forms  as  species,  and  hence  as  equivalent. 
This  is  inconvenient  enough  in  ordinary  use,  but  it  becomes  fatal  in  all  those  cases  where 
relationship  is  of  more  importance  than  the  mere  name.  These  constitute  practically 
all  the  scientific  and  practical  uses  of  plants,  in  which  genetic  relationship  arising  out 
of  evolution  is  a  matter  of  primary  concern.  In  short,  segregation  is  unscientific  because 
it  is  unnatural  and  impracticable  as  to  results,  on  account  of  its  ignoring  relationship. 
The  second  great  disadvantage  of  segregation  lies  in  the  practical  impossibility  of  recog- 
nizing most  segregates  in  the  field.  This  is  a  fatal  difficulty  in  the  case  of  all  students 
of  vegetation,  whether  ecologists  or  practical  scientists,  such  as  foresters,  grazing 
experts,  etc.  The  determination  of  the  great  majority  of  segregates  can  be  made  only 
in  the  herbarium,  if  at  all,  and  frequently  fails  of  appUcation  in  the  midst  of  the  wealth 
of  material  in  the  field. 

In  the  enormous  increase  of  unrelated  forms  treated  as  species,  segregation  constantly 
destroys  existing  knowledge  and  fails  to  add  anything  new  scientifically.  Of  the 
thousands  who  make  use  of  systematic  botany,  not  even  the  specialist  has  the  time  or 
ability  to  adjust  his  knowledge  to  each  new  segregation,  and  the  general  botanist  or 


INTRODUCTION. 


13 


practical  scientist  will  not  attempt  it.  The  steady  disappearance  of  recognized  and 
recognizable  species  removes  all  their  landmarks,  and  they  come  to  look  upon  descriptive 
botany  as  hopeless.  Their  unanimously  expressed  opinions  of  it  would  doubtless  be 
salutary,  if  these  could  only  reach  the  ears  for  which  they  are  intended.  Meanwhile, 
the  gap  between  the  systematists  and  those  they  should  serve  widens,  and  it  can  only 
be  bridged  by  a  type  of  botany  that  frankly  regards  the  needs  of  the  latter  as  paramount. 
These  needs  are  the  very  ones  that  arise  out  of  evolution  and  relationship. 

The  nature  of  the  grievance  felt  by  those  who  would  use  taxonomy  against  the  method 
of  segregation  may  be  readily  understood  by  reference  to  tables  1  and  2.  In  the  Rocky 
Mountain  region  the  number  of  species  has  increased  from  1,905  to  5,100  in  30  years, 
and  these  are  now  to  be  sought  among  950  genera  in  place  of  551.  The  species  of  91 
representative  large  genera  have  grown  from  962  to  3,576,  or  almost  fourfold.  This  is 
reflected  in  the  average  number  of  species  per  genus,  which  was  10  in  1885  and  39  in 
1917.  In  the  largest  genera  the  increase  is  often  greater;  for  example,  Eriogonum  has 
grown  from  27  species  to  122,  Salix  from  16  to  76,  Phacelia  from  6  to  44,  Krynitzkia  from 
11  to  68,  Potentilla  from  16  to  99,  Lupinus  from  13  to  80,  Aster  from  40  to  139,  Senecio 
from  21  to  114,  and  Poa  from  12  to  67.  Aconiium  with  1  species  in  1885  now  has  11, 
Dodecatheon  has  increased  from  1  to  18,  Frasera  from  1  to  11,  Gutierrezia  from  1  to  11, 
and  Chrysopsis  from  1  to  27.  In  the  case  of  Pentstemon  with  an  increase  from  27  to  98 
species,  a  further  segregation  (Pennell,  1920)  has  resulted  in  a  total  of  125  species,  and 
this  can  be  maintained  as  long  as  new  personal  judgments  are  brought  to  the  task.  This 
is  fully  confirmed  by  the  fact  that  the  species  of  1909  are  regularly  intermediate  in  number 
between  those  of  1885  and  1917.  This  total  represents  only  a  43  per  cent  increase, 
however,  while  the  number  for  1917  constitutes  a  further  increase  of  124  per  cent. 

When  definite  ecological  investigation  was  begun  in  the  Rocky  Mountains  in  1899, 
much  enthusiasm  was  felt  for  the  recently  segregated  units,  as  it  was  supposed  that  the 
contention  that  a  finer  analysis  would  be  helpful  to  the  ecologist  was  correct.  For  6 
or  8  years  an  endeavor  was  made  to  utilize  the  increasing  crop  of  segregates  in  ecological 
studies,  both  in  vegetation  and  in  experimental  evolution.  Gradually  it  became  evident 
that  the  so-called  new  species  were  herbarium-made,  and  could  not  be  expected  to  fit 
the  facts  in  the  field,  while  it  was  quickly  realized  that  they  ignored  relationships  instead 
of  suggesting  them.  In  short,  when  they  existed  outside  the  herbarium,  they  made 
correlation  difficult  or  impossible  instead  of  aiding  it.  As  a  consequence  of  this  attempt 
to  make  use  of  segregates,  it  was  realized  that  the  ecologist  could  work  only  with  more 
objective  units,  checked  by  statistics  and  experiment,  and  based  to  the  fullest  degree 
upon  evolutionary  relationship.  The  outcome  was  "Rocky  Mountain  Flowers" 
(Clements  and  Clements,  1913),  in  which  a  definite  endeavor  was  made  to  relate  the 
myriad  forms  to  definite  specific  stocks.  This  was  done  purely  from  the  ecological 
and  evolutionary  viewpoints,  and  without  any  reference  to  previous  treatments,  with 
the  exception  that  a  few  generic  segregates  were  retained  for  practical  reasons.  In  fact, 
the  earlier  treatment  of  Coulter,  which  followed  closely  that  of  Gray,  was  completely 
lost  to  view,  and  was  not  taken  into  account  until  the  preparation  of  tables  1  and  2 

Table  1. — Number  of  genera  and  species  in  Rocky  Mountain  manuals. 


Coulter, 
1885. 

Coulter  and 
Nelson,  1909. 

Rydberg, 
1917. 

Clements. 
1913. 

Genera 

551 

1,905 

331 

649 

2,733 

189 

'950 

■5,100 

0 

605 

1,878 

Species 

Varieties 

'  Extra-regional  units  excluded. 


14 


THE    PHYLOGENETIC   METHOD    IN   TAXONOMY. 


in  1920.  These  at  once  revealed  a  striking  similarity  between  the  traditional  treatment 
of  the  species  as  exemplified  by  Linnaeus,  Bentham,  Gray,  and  others  and  the  ecological 
treatment  based  upon  the  fullest  recognition  of  evolutionary  processes.  This  was  not 
merely  evident  in  the  total  number  of  species,  but  with  rare  exceptions  the  numbers 
were  also  in  close  agreement  for  the  91  genera  considered.  While  the  evidence  can 
not,  in  the  nature  of  the  case,  be  regarded  as  conclusive,  it  is  strongly  suggestive  of 
the  fact  that  the  traditional  concept  and  the  ecological  concept  of  the  species  are  based 
upon  the  same  phylogenetic  unit  and  are  essentially  identical. 

The  scientific  basis  of  species. — The  basic  essentials  of  the  evolutionary  treatment  of 
species  are  a  fixed  species  concept  and  their  determination  primarily  in  the  field.  In 
spite  of  occasional  exceptions,  the  traditional  species  concept,  crystallized  by  Linnaeus, 


Table  2. — Number  of  species  in  representalive  genera. 


Ranunculus.  . 

Aquilegia 

Delphinium . . . 

Aconitum 

Draba 

Arabis 

Lepidium 

Erysimum .  .  . . 
Lesquerella.  .  . 

Roripa 

Viola 

Geranium 

Arenaria 

Glaytonia 

Polygonum.  .  . 

Eriogonum 

Chenopodium . 

Atriplex 

Salix 

Euphorbia .  .  . . 
Dodecatheon.  . 
Polemooium..  . 

Phlox 

Gilia 

Gentiana 

Frasera 

Phacelia 

Lithospermum 
Krynitzkia. . . . 

Mertenaia 

Lappula 

Pentstemon.  .  . 

Mimulua 

Castilleia 

Pedicularia. . .  . 

Monarda 

Rosa 

Potentilla 

Fragaria 

Geum 

Lupinus 

Astragalus .  . .  . 

Aragalua 

Vicia 

Lathyrus 

Trifolium 

Saxifraga 

Heuchera 


Coulter 
and 

Nelson, 
1909. 


Rydberg, 
1917. 


Clement.3, 
1913. 


Ribes 

Quercua 

Epilobium 

Oenothera 

Mentzelia 

Opuntia 

Ligusticum 

Lomatium 

Galium 

Valeriana 

Gutierrezia 

Grindelia 

Chrysopsis 

Haplopappua . . . 
Chryaothamnua 

Solidago 

Aster 

TowQsendia. .  . . 

Erigeron 

Antennaria 

Helianthua 

Hymenopappus. 

Actinella 

Artemisia 

Arnica 

Senecio 

Carduus 

Crepis 

Agoseris 

Tradescantia .  .  . 

Allium 

Zygadenua 

Sisyrinchium .  .  . 

Juncus 

Carex 

Agrostis 

Stipa 

Poa 

Featuca 

Bromus 

Agropyrum .  .  .  . 
Elymus 

Total 

Average  No.  of 
species  per 
genus 


Coulter, 
1885. 


Coulter 

and 
Nelson, 
1909. 


Rydberg, 
1917. 


elements, 
1913. 


5 

1 

35 

8 

11 

4 

37 

21 

62 

47 

20 

6 

7 

3 

INTRODUCTION.  16 

gave  fairly  uniform  and  thoroughly  usable  results  in  the  hands  of  many  workers  for  more 
than  a  century  and  a  half.  Even  though  supported  chiefly  by  tradition,  it  has  provided 
a  stable  basis  for  species  that  was  quickly  lost  when  segregation  became  the  usual  prac- 
tice. However,  preliminary  statistical  and  experimental  studies  indicate  that  the 
traditional  concept  was  in  essential  agreement  with  the  evolution  of  specific  stocks,  while 
the  concept  used  in  segregation  yielded  only  minor  and  recent  modifications  of  this 
stock.  With  respect  to  convenience  and  usabiUty,  the  traditional  concept  has  everything 
in  its  favor,  in  that  it  builds  upon  existing  knowledge,  permits  the  recognition  of  few 
new  species  in  well-known  floras,  assigns  definite  limits  characterized  as  a  rule  by  actual 
gaps  in  evolution,  and  affords  the  opportunity  to  relate  minor  variations  to  the  major 
stock.  As  already  indicated,  the  concept  applied  in  segregation  enormously  increases 
the  number  of  species,  overwhelms  specific  stocks  in  a  flood  of  segregates  of  all  possible 
values,  and  thus  destroys  or  obscures  the  main  body  of  taxonomic  knowledge.  Conse- 
quently, if  taxonomy  is  to  be  either  stable  or  usable,  it  must  still  rest  upon  the  species 
concept  of  Linnaeus  and  the  practice  of  eminent  taxonomists  from  his  time  to  the  present. 
No  change  of  concept  can  be  made  on  scientific  grounds  until  the  species  so  founded 
have  been  tested  by  statistics  and  experiment,  and  the  evidence  at  present  available 
indicates  that  these  methods  will  confirm  rather  than  modify  the  traditional  and  the 
evolutionary  view  of  the  species  (cf.  Clausen,  1922). 

The  thesis  that  species  can  be  recognized  only  in  the  field  would  seem  to  require  no 
argument,  were  it  not  for  the  fact  that  they  are  seldom  made  there.  It  is  probable  that 
few  taxonomists  would  take  exception  to  this  statement,  but  many  would  question  the 
practicability  of  the  field  method,  and  would  incline  to  regard  occasional  collecting  trips 
as  a  fair  substitute.  Moreover,  custom  itself  furnishes  a  strong  argument  in  favor  of 
the  herbarium  as  the  place  for  recognizing  species.  These  have  always  been  "made"  in 
the  herbarium;  why  not  continue  to  make  them  there?  Reasons  of  convenience  tell 
most  strongly  in  favor  of  continuing  this  practice.  The  field  is  often  distant,  and  the 
expense  of  field  work  heavy  if  not  prohibitive.  The  field  is  available  for  work  but  a 
small  part  of  the  year  in  many  regions,  and  personal  convenience,  as  well  as  such  duties 
as  teaching,  is  often  a  deciding  factor.  Moreover,  one  works  much  faster  by  the  her- 
barium method,  and  results  accumulate  much  more  rapidly.  An  even  more  cogent 
reason  is  the  fact  that  types  are  available  only  in  herbaria,  and  it  is  natural  to  feel  that 
critical  work  can  be  done  only  in  contact  with  them.  However,  the  most  compelling 
reason  is  that  of  tradition  and  custom,  combined  with  the  fact  that  no  field  method  has 
heretofore  been  developed  for  the  study  of  species.  With  this  available,  it  is  confidently 
to  be  expected  that  taxonomy,  like  other  scientific  subjects,  will  turn  to  the  field  as  the 
one  place  in  which  material  and  process  are  fully  available,  and  in  which  results  will 
meet  the  most  critical  requirements  as  to  scientific  quality  and  permanence. 

From  the  above,  it  follows  that  evolutionary  taxonomy  must  regard  the  segregates 
of  the  last  25  years  chiefly  in  the  light  of  tentative  proposals  as  to  the  course  of  evolution. 
It  is  imperative  to  reestablish  species  on  the  basis  of  the  traditional  concept  as  exemplified 
in  America  by  Gray  and  those  that  have  worked  in  a  similar  manner  since.  The  fact 
is  not  ignored  that  all  the  master  taxonomists  recognized  some  forms  that  were  not  species 
according  to  their  own  concept  (Chase,  1921),  but  this  was  exceptional  and  had  no  appre- 
ciable effect  on  the  body  of  their  species.  The  apphcation  of  statistics  and  experiment 
to  certain  species  of  the  "Synoptical  Flora"  has  shown  that  a  relatively  small  number 
are  to  be  treated  as  variads.  It  is  significant  of  Gray's  concept  and  the  basis  of  relation- 
ship behind  it  that  in  nearly  every  doubtful  case  he  pointed  out  the  inadequacy  of  the 
form  as  a  species.  These  are  the  first  of  which  the  validity  requires  statistical  test,  in 
order  that  a  coherent  and  uniform  body  of  species  that  meet  the  evloutionary  demands 
may  be  established.     Even  before  this  is  completed,  however,  it  is  possible  and  desirable 


16  THE    PHYLOGENETIC   METHOD    IN   TAXONOMY. 

to  begin  the  evolutionary  analysis  of  valid  species,  and  to  take  existing  segregates  into 
account  in  doing  this,  as  in  the  present  monograph.  For  the  immediate  present,  it  must 
suffice  to  treat  all  primary  modifications  of  the  specific  stock  as  subspecies,  though  it  is 
known  that  these  are  not  equal  in  rank  or  identical  in  origin,  a  subject  that  is  further 
discussed  on  page  23. 

In  this  connection  it  is  becoming  clearer  that  the  herbarium  type  is  always  an  inade- 
quate and  often  a  misleading  representative  of  its  species.  It  is  merely  an  accident  if 
it  happens  to  represent  the  species  as  found  in  the  field,  and  in  one  undergoing  active 
evolution  it  can  only  suggest  one  variad  out  of  many.  In  statistical  and  experimental 
studies  of  the  species,  the  herbarium  type  will  retain  historical  value  alone,  and  the 
actual  type  will  consist  of  a  statistical  expression  drawn  from  hundreds  if  not  thousands 
of  individuals,  and  hence  available  to  workers  all  over  the  world. 

NOMENCLATURE. 

Purpose  and  value. — A  uniform  and  stable  nomenclature  has  been  the  goal  of  systematic 
botanists  for  more  than  a  half-century,  and  especially  since  the  appearance  of  Kuntze's 
' '  Revisio  Generum  Plantarum  "  in  1 89 1 .  Uniformity  has  been  less  sought  than  stability, 
and  the  latter  has  come  to  be  linked  generally  with  priority.  It  is  beside  the  purpose 
of  the  present  discussion  to  deal  with  the  various  proposals  for  securing  stability  and  their 
divergent  results,  though  the  fact  can  not  be  ignored  that  all  of  these  have  signally  failed 
of  their  purpose.  It  now  appears  certain  that  priority,  attractive  as  it  seems  in  the 
abstract,  has  failed  finally  to  obtain  recognition  as  the  absolute  rule  of  nomenclature, 
and  it  may  confidently  be  expected  that  nomenclature  will  pay  increasing  attention  to 
other  matters,  quite  as  important  as  a  stereotyped  stabihty.  In  fact,  it  seems  never 
to  have  been  realized  that  stability  was  destroyed  more  rapidly  by  the  method  of  segre- 
gation than  it  could  be  established  by  the  rules  of  nomenclature. 

The  primary  purpose  of  nomenclature  is  to  provide  an  accurate  and  convenient  way 
of  designating  genera  and  species,  as  well  as  variads  and  their  forms.  In  the  past,  the 
emphasis  has  been  placed  upon  accuracy  with  little  thought  of  convenience,  probably 
because  stability  has  been  a  fetish  before  which  all  other  considerations  disappeared. 
The  phrase,  "A  name's  a  name"  has  been  used  to  justify  the  position  that  the  botanist 
need  concern  himself  no  further  than  to  apply  any  name  he  chose,  regardless  of  all 
considerations  except  that  of  previous  use.  This  has  been  one  of  the  most  unfortunate 
features  of  the  usual  attitude  of  specialists,  and  is  largely  responsible  for  the  feeling  of 
most  scientists  and  practically  all  laymen  toward  the  subject.  To  them  it  is  merely 
a  mass  of  hard  names,  with  but  a  sUght  appreciation  of  the  needs  of  those  who  would 
like  to  know  plants.  This  lack  of  vision  and  sympathy  has  been  one  of  the  greatest 
handicaps  of  the  systematist,  and  it  is  the  chief  reason  why  nomenclature  requires  modi- 
fication and  improvement.  Here,  no  more  than  in  the  recognition  of  species  can  personal 
judgment  or  the  lack  of  it  be  regarded  as  the  final  arbiter  in  the  matter  of  names. 
Thousands  of  names  have  no  further  justification  than  the  caprice  of  the  describer,  and 
hundreds  of  them  are  completely  lacking  in  every  canon  of  convenience  and  good  taste. 
Indeed,  taxonomy  is  the  only  field  of  science  in  which  the  blunders  and  banaUties  of  the 
indifferent  and  incompetent  are  respected  and  perpetuated. 

Future  role. — It  is  as  inevitable  as  it  is  unfortunate  that  the  names  of  plants  should 
be  made  by  systematists  for  systematists.  Since  the  latter  possess  all  possible  degrees 
of  competence  and  good  taste,  it  is  natural  that  the  standard  for  names  should  be  low  and 
that  these  should  need  the  protection  of  codes  to  maintain  themselves.  The  final 
stage  in  this  respect  is  reached  when  it  is  provided  that  the  blunders  of  the  printer  are 
to  be  corrected,  but  those  of  the  author  are  not!  Such  rules  seem  futile,  since  increasingly 
high  standards  of  scientific  performance  and  scientific  service  in  the  future  will  cause 


INTRODUCTION.  17 

them  to  be  more  and  more  ignored.  There  are  several  cogent  reasons  why  nomenclature 
should  concern  itself  less  with  a  fugitive  stability  derived  from  rules  and  give  much  more 
attention  to  one  based  upon  excellence  and  usability.  In  the  first  place,  it  seems  clear 
that  the  rights  of  thousands  of  users  outweigh  those  of  the  scores  of  systematists,  and 
that  usability  and  attractiveness  must  rank  with  stability  as  primary  qualities  of  a  nomen- 
clature. This  is  strikingly  true  when  the  future  is  weighed  against  the  present,  and  it  is 
realized  that  the  codes  of  to-day  would  fix  existing  conditions  for  all  time.  While  there 
seems  little  danger  of  this  to  one  who  believes  that  the  methods  and  results  of  each 
generation  of  scientists  will  show  an  advance  upon  those  of  the  preceding,  it  is  unfortunate 
that  «iany  systematists  appear  to  feel  that  nomenclature  is  a  thing  apart  from  science, 
and  that  progress  in  it  can  be  prevented  by  codes. 

Essentials  of  stability. — Those  who  hoped  that  application  of  the  rule  of  priority 
would  lead  to  a  stable  and  universal  nomenclature  in  a  few  years  have  been  greatly  disap- 
pointed and  have  come  to  realize  that  strict  priority  affords  a  less  practicable  basis  than 
usage.  The  outcome  for  the  flowering  plants  is  still  in  doubt,  but  it  is  suggested  by 
practically  all  the  proposals  for  securing  stability  among  the  cryptogams,  which  agree 
in  selecting  starting-points  that  will  disturb  usage  little  or  not  at  all.  In  the  very  nature 
of  the  case,  greater  stabihty  is  obtained  by  taking  advantage  of  usage  than  by  going 
counter  to  it.  While  to  many,  priority  has  seemed  to  have  some  special  virtue  as  a 
basis  for  nomenclature,  its  merit  must  be  measured  by  its  practicability,  and  by  this 
test  it  is  little  if  any  better  than  usage.  This  is  best  shown  by  the  fact  that  even  the 
most  thoroughgoing  priority,  that  dating  from  the  "Species  Plantarum,"  is  based 
upon  usage  in  that  it  ignores  all  previous  work. 

To  some  systematists  stability  has  seemed  to  be  achieved  when  the  adherents  of  a 
particular  code  were  in  essential  agreement  as  to  its  concrete  application,  a  condition 
not  always  met.  As  an  actual  fact,  however,  stability  exists  only  when  a  particular 
code  of  rules  has  universal  sanction  and  gives  the  same  results  in  application.  Such  a 
condition  seems  distant  at  present,  and  for  many  reasons  it  is  to  be  hoped  that  it  will 
not  come  about  until  systematists  have  a  wider  vision  and  truer  perspective  in  matters 
of  nomenclature.  A  further  reason  why  stability  is  a  will-o-the-wisp  lies  in  the  effect 
of  segregation,  for  it  must  be  recognized  that  stability  consists  as  much  in  having  the 
same  unit  for  a  name  as  in  having  the  same  name  for  a  unit.  It  lies  also  in  respecting 
existing  landmarks  and  in  relating  all  new  knowledge  to  these.  This  in  itself  involves 
a  thorough  change  in  the  current  practice,  at  least  in  America,  and  demands  that  the 
trinomial  be  brought  into  regular  use  for  segregates  of  valid  species.  The  binomial 
should  be  restricted  to  the  species  as  including  all  of  its  subspecies,  and  the  trinomial 
would  always  serve  to  distinguish  the  subspecies  and  to  relate  it  to  its  proper  specific 
stock  (cf.  Clausen,  1922).  Finally,  it  seems  impossible  to  think  that  blundering,  mean- 
ingless, or  excessively  long  names  can  be  stabilized.  They  detract  from  the  value  and 
usability  of  taxonomy,  as  well  as  its  attractiveness,  and  true  stability  can  be  obtained 
only  by  correcting  or  ignoring  them. 

Practical  nomenclature. — If  the  names  of  plants  are  to  meet  the  needs  of  all  those  that 
use  taxonomy  or  would  use  it,  they  should  be  brief,  significant,  well-constructed,  and 
euphonic.  In  the  present  series  of  monographs  an  endeavor  is  made  to  secure  maximum 
currency  for  the  names  used  by  taking  into  account  the  needs  of  the  amateur  and  the 
general  scientist  as  well  as  those  of  the  specialist.  This  is  achieved  in  the  first  place 
by  retaining  the  traditional  species,  under  which  the  segregates  are  assembled,  while 
the  names  of  the  latter  are  retained  in  so  far  as  their  quality  permits.  Even  while  much 
latitude  in  regard  to  varietal  and  subspecific  names  is  allowed  by  both  codes,  continuity 
is  the  essence  of  stability,  and  this  can  be  secured  only  by  retaining  names  whenever 
possible.     Because  of  its  greater  emphasis  upon  usage,  the  International  Code  has 


18  THE    PHYLOGENETIC   METHOD    IN   TAXONOMY. 

been  followed  in  the  main,  wherever  it  is  consistent  with  the  principles  adopted  here. 
However,  there  has  been  no  hesitation  in  selecting  names  from  those  valid  under  the 
American  Code  when  these  are  preferable,  and  no  compunction  has  been  felt  in  using 
names  sanctioned  by  neither  code  when  this  has  been  found  to  be  in  the  interests  of 
usefulness.  To  the  conservative  adherents  of  either  code  this  may  seem  reprehensible, 
but  there  are  many  indications  that  it  will  be  welcomed  by  the  vast  majority  of  non- 
specialists,  who  are  much  more  interested  in  short  significant  names  than  they  are  in 
validity  as  determined  by  codes.  It  should  be  added,  however,  that  in  the  present  mono- 
graphs it  has  been  found  necessary  to  depart  from  the  rules  of  the  International  Code  in 
but  few  cases  and  that  the  number  of  names  not  in  agreement  with  either  code  does  not 
exceed  two  or  three.  All  departures  from  the  International  Code  are  clearly  indicated 
in  the  text. 

Invalid  and  corrected  names. — Undesirable  practices  in  nomenclature  have  been 
discussed  at  length  by  Clements  (1902),  and  here  it  will  suffice  to  point  out  those  that 
are  regarded  as  rendering  names  invalid  or  subject  to  correction.  The  number  of  unde- 
sirable names  is  relatively  small,  and  their  correction  is  based  upon  the  contention  that 
usability  and  uniformity  are  the  first  considerations.  Furthermore,  corrections  should 
not  be  a  matter  of  individual  judgment,  but  should  be  in  harmony  with  current  good 
usage.  Thus,  in  the  matter  of  transliteration,  it  is  probable  that  99  per  cent  of  all  Greek 
names  are  properly  transliterated  into  Latin,  and  there  is  no  valid  reason  for  not  changing 
the  others  to  correspond.  Similarly,  all  incorrect  spellings  should  be  changed  to  conform 
to  the  best  usage,  and  it  is  contended  that  an  author  has  no  more  right  to  spell  improperly 
than  has  a  printer.  Names  of  great  length,  which  are  fittingly  termed  sesquipedalian, 
should  be  shortened  when  more  than  six  syllables  long.  Specific  names  ending  in 
-folia  are  especial  offenders  in  this  respect,  and  are  readily  shortened  without  violence 
by  dropping  the  last  term. 

The  most  serious  offenses  against  good  usage  are  found  in  hybrid  and  vernacular  names, 
and  in  anagrams.  To  mention  such  names  as  Henningsocarpum,  Radlkofertoma,  and 
Schweinfurthafra  is  to  condemn  them.  They  can  have  no  standing  with  those  who  believe 
that  the  rights  of  the  many  are  paramount  to  those  of  the  few,  and  that  usability  and 
good  taste  are  at  least  as  important  as  priority.  The  cost  of  the  latter  is  also  well  illus- 
trated by  such  doublets  as  Symphoricarpus  symphoricarpus  and  Grossularia  grossularia, 
which  are  rejected  by  one  code  but  supported  by  another. 

Essentials  of  usability. — It  has  repeatedly  been  emphasized  that  a  nomenclature  must 
be  judged  by  its  value  to  its  users  rather  than  to  its  makers.  From  this  standpoint 
brevity  and  significance  are  the  very  essence  of  nomenclature,  though  structure,  euphony, 
and  uniformity  are  not  to  be  ignored.  Five  syllables  should  constitute  the  maximum 
length  for  generic  or  specific  names,  and  three  or  four  should  be  the  optimum.  No 
name  should  be  regarded  as  desirable  that  does  not  bear  a  direct  application  to  the 
structure,  habit,  or  behavior  of  the  plant  or  some  part  of  it.  It  is  idle  to  cavil  at  such 
names  as  canadensis,  caroliniana,  etc.,  for  species  that  occur  throughout  the  Middle 
West,  since  they  were  geographically  applicable  at  the  time  given.  However,  they  prove 
the  undesirability  of  geographical  names,  which,  like  personal  ones,  should  be  avoided. 
This  applies  equally  to  vernacular  terms,  though  in  all  these  cases  existing  names  should 
be  retained,  except  when  seriously  at  fault.  As  to  structure  and  euphony,  future  practice 
should  adhere  closely  to  general  good  usage,  while  existing  names  should  be  corrected 
when  necessary.  When  there  is  a  choice  between  a  good  name  and  one  distinctly  bad, 
no  one  should  hesitate  to  use  the  former,  notwithstanding  the  rule  of  priority.  Euphony 
and  brevity  are  most  frequently  ignored  in  the  case  of  personal  and  vernacular  names, 
such  as  Krasheninnikoviana,  Niedzwetzkyana,  Turczaninoviana,  Wosnessenskia,  and 
Zaluzianskya,  and  the  ultimate  rejection  of  such  handicaps  to  taxonomy  seems  inevitable. 


INTRODUCTION.  19 

Finally,  the  user  of  names  has  the  right  to  expect  them  to  be  as  uniform  and  simple  as 
possible.  Initial  h  should  never  be  lost,  as  frequently  occurs  in  Haplopappus,  Heleocharis, 
etc.,  and  in  the  case  of  permissible  alternatives,  as  in  the  genitive,  the  simpler  form  is 
always  preferred,  e.  g.,  nuttalli,  parishi,  etc. 

A  binomial  system  of  common  names. — The  realization  of  the  fact  that  the  vast  majority 
of  people  make  their  contacts  with  plants  only  through  the  common  names  seems  to 
render  a  more  adequate  system  imperative.  Most  of  the  so-called  common  names  of 
the  manuals  are  not  vernacular  names  at  all,  but  mere  translations  of  the  technical  name. 
They  possess  no  currency,  and  lack  the  qualities  to  secure  it.  A  few  of  the  actual  ver- 
nacular names  are  excellent,  but  most  of  them  are  either  local,  misapplied,  or  entirely 
without  significance.  When  significant  common  names  are  in  general  use,  they  should 
be  worked  into  a  comprehensive  system  wherever  possible.  The  most  serious  failures 
of  vernacular  names  are  in  failing  to  show  relationship  and  to  make  specific  distinctions. 
In  endeavoring  to  secure  these  values,  it  quickly  became  evident  that  the  binomial  was 
as  indispensable  for  common  names  as  for  technical  ones.  In  constructing  a  binomial 
system,  the  current  name  for  the  genus  or  one  of  its  most  important  species  was  taken  as 
the  basis,  and  the  specific  term  was  used  in  a  compound  or  as  a  modifier.  The  one  case 
is  illustrated  by  Atriplex,  in  which  the  generic  term,  scale,  was  derived  from  shadscale, 
the  current  name  for  A.  conferiifolia,  and  similar  names  made  for  the  other  important 
species,  e.  g.,  wingscale  for  A.  canescens,  lenscale  for  A.  lentiformis,  allscale  for  A.  poly- 
carpa,  etc.  The  other  is  exemplified  by  Artemisia,  in  which  the  current  name  for  the 
genus,  sagebrush,  is  modified  by  a  specific  epithet  in  the  case  of  all  the  shrubby  species 
but  A.  tridentata,  e.  g.,  hoary  sagebrush  for  A.  cana,  sand  sagebrush  for  A.  filifolia, 
coast  sagebrush  for  A.  calif ornica,  etc.  The  term  sagewort  is  applied  to  the  herbaceous 
species  in  a  similar  manner,  e.  g.,  dragon  sagewort  for  A.  dracunculus,  field  sagewort 
for  A.  campestris,  etc. 

METHODS  AND  RESULTS  IN  EVOLUTIONARY  TAXONOMY. 

Methods. — The  conviction  has  been  repeatedly  expressed  that  taxonomy  to  be  phylo- 
genetic  and  permanent  must  be  based  upon  the  field  as  the  primary  seat  of  investigation. 
It  is  conceivable  that  hundreds  of  individuals  representing  the  whole  range  of  variation 
and  adaptation  might  be  specially  collected  and  made  use  of  in  the  herbarium,  but  this 
is  beyond  the  bounds  of  practicability.  This  does  not  mean  that  the  actual  measure- 
ments involved  in  statistical  studies  will  not  be  made  indoors,  but  the  specific  analysis 
that  precedes  this  is  preeminently  a  field  process.  The  field  here  is  conceived  in  no  narrow 
sense,  but  it  includes  greenhouse,  garden,  field  inclosure,  and  in  fact  all  habitats,  natural 
or  artificial,  in  which  the  evolutionary  behavior  of  living  plants  can  be  studied.  The 
complete  field  method  demands  a  knowledge  of  the  variation  of  the  species  concerned 
throughout  its  climatic  area  and  of  its  adaptation  as  it  enters  diverse  habitats  adjacent 
to  the  normal  one.  It  further  requires  statistical  studies  of  the  species  and  its  variads 
in  the  whole  range  of  natural  conditions,  and  experimental  analysis  in  controlled  natural 
habitats  as  well  as  in  garden  and  greenhouse.  It  is  obviously  a  method  that  demands 
much  and  yields  much  in  return.  It  needs  field  laboratories  and  transplant  stations, 
and  is  impossible  of  use  in  collecting  trips  and  reconnoissance.  As  a  consequence,  it  is 
little  adapted  to  the  preUminary  organization  of  the  flora  of  new  or  little-known  countries, 
but  it  is  indispensable  in  testing  and  refining  such  results  to  the  point  where  they 
accurately  represent  the  facts  of  evolution  and  relationship. 

Statistics. — The  statistical  study  of  the  degree  of  modification,  as  shown  by  the  indivi- 
duals of  a  species  or  a  variad,  yields  results  of  the  most  fundamental  importance,  an 
importance  surpassed  only  by  those  obtained  from  experiment.  The  first  of  these  is  a 
far  more  exact  expression  of  the  stage  of  evolution  attained  collectively  than  the  most 


20  THE  PHYLOGENETIC  METHOD  IN  TAXONOMY. 

accurate  judgment  is  capable  of,  together  with  a  clear  indication  of  the  relation  to 
adjacent  units  as  revealed  by  the  bases  of  the  curve.  Of  equal  importance  is  the  evidence 
furnished  by  the  modes  as  to  the  direction  of  evolutionary  movement.  This  is  true  not 
only  of  the  species  or  variad,  but  also  of  the  criteria  themselves,  and  one  of  the  most 
significant  services  of  the  statistical  method  is  the  opportunity  it  affords  of  scrutinizing 
criteria  as  they  occur  in  nature.  This  constitutes  an  invaluable  service  at  this  time,  when 
experiment  is  still  too  rare  to  provide  the  results  desired.  The  testing  of  criteria  should 
be  the  first  task  of  quantitative  studies,  were  it  not  for  the  fact  that  this  can  be  done  at 
the  same  time  that  the  modes  and  limits  of  species  and  variads  are  determined. 

The  methods  of  statistical  analysis  can  be  applied  equally  well  to  species  and  their 
variants  as  they  exist  in  nature,  to  results  of  such  outstanding  natural  experiments  as 
ecads,  and  to  the  forms  obtained  by  experiments  under  control.  However,  the  chief 
value  at  present  Ues  in  the  application  to  the  study  of  variation  as  it  occurs  in  nature, 
owing  to  the  enormous  mass  of  material  demanding  analysis.  In  this  it  is  of  the  greatest 
value  in  determining  whether  a  segregate  represents  an  actual  fact  of  evolution  and  in 
confirming  its  suggested  relationship  to  the  species  as  well  as  the  nearest  variads.  While 
the  statistical  method  applies  only  to  characters  that  can  be  measured  or  counted,  or  to 
sequences,  these  are  found  to  include  practically  all  characters  of  importance  in  species 
and  variads.  It  demands  a  large  amount  of  material  to  insure  the  most  accurate  and 
comprehensive  results,  and  the  selection  of  this  is  of  the  first  consequence.  Random 
selection  is  without  value  for  careful  analysis,  and  gives  usable  results  only  where  it  is 
wished  to  obtain  merely  the  total  range  of  variation  in  a  particular  area  or  locality. 
A  preliminary  examination  is  indispensable  to  permit  the  recognition  of  variants  and 
ecads,  and  to  insure  that  the  analysis  runs  parallel  with  these  instead  of  cutting  across 
them.  While  analysis  on  the  spot  is  always  desirable,  owing  to  the  abundance  of  material 
or  the  opportunity  of  checking,  both  as  to  forms  and  habitat  factors,  this  is  possible  only 
at  field  laboratories  and  substations.  In  the  case  of  regions  remote  from  these,  material 
must  be  collected  with  the  maximum  discrimination,  and  with  especial  reference  to  the 
object  sought.  This  may  be  the  range  of  variation  of  any  character  or  any  organ  with 
respect  to  the  individual,  community,  species,  or  variad.  The  use  of  fresh  material  is 
always  preferable,  but  often  impossible,  and  the  question  of  the  use  of  dried  or  preserved 
material  depends  somewhat  upon  the  plant  and  part  concerned,  as  well  as  upon  facilities. 
The  chief  precaution  necessary  is  to  measure  while  living  a  few  of  the  parts  to  be  studied, 
in  order  to  check  out  any  alteration  of  size  due  to  the  method  of  preservation.  As 
statistical  methods  come  more  into  use  in  evolutionary  taxonomy,  the  results  will  be 
regularly  expressed  in  biometrical  form,  but  at  present  tabulations  and  simple  graphs 
furnish  all  the  facts  required. 

Experiment. — The  r61e  of  experiment  in  evolutionary  taxonomy  is  even  more  funda- 
mental than  that  of  statistics,  though  in  the  beginning  it  rather  supplements  the  latter, 
owing  to  the  time  involved  in  complete  experiments.  Its  unique  importance  hes  partly 
in  the  control  possible  throughout  the  entire  process,  but  it  arises  chiefly  from  the  fact 
that  it  alone  yields  conclusive  evidence  as  to  descent.  The  exact  use  of  statistical 
methods  affords  practical  certainty  as  to  the  origin  and  relationship  of  variads,  for 
example,  but  the  actual  origin  has  already  occurred,  and  its  nature  and  causes  can  only 
be  inferred.  To  bridge  this  gap,  experiment  is  indispensable,  and  hence  it  must  be  the 
final  arbiter  in  all  questions  of  origin  and  descent.  In  actual  practice,  experiment  is 
begun  with  the  statistical  studies  or  as  soon  after  as  possible,  and  the  two  are  carried 
forward  hand  in  hand,  so  that  each  may  profit  from  the  other. 

As  a  matter  of  convenience,  experiments  may  be  designated  as  natural  and  artificial, 
though  the  line  between  them  is  slight.  Natural  experiments  are  those  in  which  various 
migration  agents  have  carried  migrules  into  adjacent  habitats  and  the  individuals  have 


INTRODUCTION.  21 

undergone  definite  adaptation  to  the  controlling  factor  and  have  become  ecads.  In 
cases  where  the  migration  is  interrupted,  the  question  of  descent  lacks  the  final  degree 
of  certainty  where  more  than  one  parent  species  may  be  concerned.  In  mountain  regions 
where  the  topography  is  rugged  and  rapidly  changing,  habitats  are  so  fragmented  that 
they  recur  again  and  again  in  the  same  relation  to  each  other.  This  offers  ideal  conditions 
for  the  invasion  of  new  habitats,  and  the  ecads  of  plastic  species  occur  repeatedly.  In 
many  cases,  gravity  is  the  migration  agent,  and  in  others  the  annual  extension  of  root- 
stock  or  runner  brings  about  invasion.  In  both  instances  there  is  not  only  complete 
continuity  in  space,  but  often  also  in  time,  so  that  the  question  of  the  specific  stock  from 
which  the  ecad  has  sprung  is  as  certain  as  in  experiments  started  artificially. 

Artificial  experiments  differ  from  natural  ones  chiefly  in  that  the  question  of  origin 
is  always  a  matter  of  certainty.  They  differ  also  in  being  carried  on  necessarily  under 
control,  owing  to  the  fact  that  the  number  of  individuals  is  limited,  and  no  chances  can 
be  taken  with  their  loss.  In  nature  there  may  be  a  hundred  or  a  thousand  individuals 
of  an  ecad  in  one  spot,  and  this  may  occur  repeatedly  in  a  restricted  mountain  region. 
Thus,  while  it  is  sometimes  desirable  to  protect  a  particular  group  from  rodents,  for 
example,  it  is  rarely  necessary.  In  artificial  experiments,  control  and  natural  conditions 
are  often  antagonistic,  and  the  decision  between  them  must  be  made  upon  the  basis  of 
the  results  desired.  In  the  case  of  hybridization  this  difficulty  does  not  exist,  since 
physical  factors  are  not  taken  into  account,  and  investigations  of  this  process  are  espe- 
cially adapted  to  garden  and  greenhouse.  On  the  other  hand,  the  origin  and  differen- 
tiation of  existing  species  and  ecads  can  best  be  studied  in  the  field,  as  garden  and 
greenhouse  conditions  can  only  be  made  to  approximate  natural  habitats  at  the  best. 
However,  the  plasticity  of  species  and  their  reaction  to  known  factors  furnish  admirable 
subjects  for  study  under  complete  control,  and  certain  aspects  of  mutation  are  also  best 
studied  in  this  manner. 

In  experiments  at  the  Alpine  Laboratory,  where  the  chance  of  disturbance  by  man 
is  slight,  the  degree  of  control  has  varied.  Grasses  and  cacti  require  little  protection  in 
a  region  without  grazing,  and  the  garden  of  plains  species  has  not  been  fenced.  In  the 
case  of  reciprocal  transplants,  it  has  not  seemed  practicable  to  protect  each  scattered 
individual  with  wire  netting.  With  alpine  plants,  however,  their  early  appearance  and 
succulence,  as  well  as  the  labor  involved  in  transplanting,  has  made  it  necessary  to  fence 
the  gardens  against  rodents  from  the  first.  This  involves  practically  no  change  of  the 
physical  factors,  if  plants  are  kept  away  from  the  sides  of  the  fence  toward  the  sun, 
and  the  experience  of  several  years  indicates  that  all  transplants  and  other  field  experi- 
ments can  well  be  fenced,  except  in  the  case  of  natural  experiments  involving  many 
individuals.  The  hazards  of  weather,  such  as  hail  and  flood,  alone  work  sufficient 
damage,  and  against  these  there  is  no  protection  that  does  not  change  conditions.  The 
fencing  of  reciprocal  transplants  requires  especial  care  to  see  that  the  plant  is  at  no  times 
shaded  by  the  netting  or  harmed  by  the  wind.  Finally,  adequate  control  in  the  case 
of  transplants  requires  the  reduction  or  eUmination  of  competition  where  they  are 
planted  into  other  communities,  since  this  involves  a  factor  not  readily  measured. 

Method  of  experiment— The  primary  methods  of  experiment  in  the  field  are  trans- 
planting, planting,  seeding,  and  modification  of  the  habitat.  The  details  of  these  methods 
belong  in  another  place,  and  it  will  suffice  here  to  point  out  their  differences  and  values. 
Transplanting  consists  in  transferring  the  adult  plant  from  one  climate,  habitat,  or 
situation  to  another.  It  is  reciprocal  when  two  related  species,  a  species  and  its  variad, 
or  two  related  variads  are  concerned.  Climatic  transplants  are  those  in  which  a  species 
is  transferred  from  one  climate  or  subclimate  to  another  or  to  more  than  one,  as  when 
alpine  species  are  moved  to  the  montane  and  plains  region,  or  a  dominant  of  the  true 
prairie  to  the  mixed  prairie  and  the  bunch-grass  prairie.     Habitat  or  edaphic  transplants 


22  THE    PHYLOGENETIC   METHOD    IN    TAXONOMY. 

deal  primarily  with  the  transfer  within  the  habitats  of  the  same  climax,  i.  e.,  between 
the  climax  and  one  or  more  serai  habitats,  or  the  latter  alone.  Such  transplants  are 
especially  advantageous,  as  they  are  made  with  the  minimum  of  labor,  and  usually  give 
the  most  striking  results  in  the  form  of  ecads.  Planting  seedlings  from  the  greenhouse 
or  nursery,  or  sowing  seeds  under  proper  precautions,  takes  advantage  of  the  fact  that 
the  seedling  is  usually  more  plastic  than  the  adult,  but  it  is  subject  to  many  more 
dangers  during  ecesis.  Consequently,  while  they  are  standard  methods  in  experi- 
mental vegetation,  they  are  little  used  as  yet  in  experimental  evolution.  The 
modification  of  the  habitat  is  one  of  the  best  of  methods,  chiefly  because  it  permits 
the  modification  of  a  whole  group  of  individuals  in  position.  It  is  further  valuable  in 
furnishing  a  check  upon  the  behavior  of  related  individuals  transplanted  to  conditions 
similar  to  those  produced  by  the  modification.  Its  one  disadvantage  lies  in  the  labor 
sometimes  involved  in  bringing  about  an  effective  change  of  conditions,  especially  in 
forests.  In  such  cases,  however,  Nature  frequently  steps  in  and  brings  about  the 
desired  result  by  the  fall  of  a  tree,  by  fire,  or  wind-throw.  In  woodland,  scrub,  grassland, 
or  herbaceous  communities  it  is  often  an  easy  task  to  change  efifectively  the  light  inten- 
sity, water-content,  air-content,  etc. 

In  the  case  of  reciprocal  transplants,  it  is  fairly  certain  that  conditions  will  not  be  too 
extreme  for  either  plant,  but  with  climatic  and  edaphic  transplants  there  is  no  definite 
assurance,  at  least  in  the  beginning.  To  obviate  this,  a  transplant  sequence  is  used, 
by  which  plants  are  transferred  to  one  or  more  intermediate  zones  or  habitats.  If 
conditions  are  too  extreme  in  the  last  situation  of  the  series  and  the  plants  are  lost,  those 
of  the  next  less  extreme  habitat  will  serve  to  show  the  limits  of  adaptation.  When 
plants  are  not  plastic,  however,extreme  conditions  furnish  the  only  method  of  breaking 
the  structural  habit  and  thus  permitting  adaptation  (cf.  Turesson,  1922). 

As  already  indicated,  a  certain  amount  of  control  can  be  exerted  over  physical  factors 
in  the  case  of  field  experiments.  With  respect  to  the  primary  factor,  this  is  secured 
when  the  water-content  of  an  area  is  increased  or  diminished,  or  the  light  intensity 
changed  by  clearing  or  shading,  especially  when  part  of  the  group  or  community  is  left 
under  the  original  conditions  to  serve  as  a  check.  In  a  sense,  moreover,  a  kind  of  control 
is  assured  when  plants  are  transferred  from  sun  to  shade  or  from  wet  to  dry.  Garden 
experiments  resemble  those  in  the  field  in  the  extent  to  which  factors  can  be  controlled 
or  manipulated,  and  in  both  complete  measurements  of  all  the  major  factors  are  indis- 
pensable. In  the  greenhouse,  the  opportunities  for  control  and  manipulation  are  much 
greater,  and  studies  of  adaptation  to  definite  amounts  of  factor  stimuli  can  be  carried 
on  with  much  greater  convenience  and  certainty,  especially  where  a  sequence  of  intensities 
is  desired.  The  greenhouse  makes  it  possible  to  equalize  in  large  degree  all  the  factors 
except  the  one  to  be  studied,  and  thus  permits  the  more  exact  causal  analysis  of  results 
obtained  in  the  field.  For  this,  measurement  of  the  factors  is  as  indispensable  as  in 
the  field,  since  this  alone  permits  the  correlation  of  definite  quantities  of  response  with 
equally  definite  amounts  of  the  controlling  factor. 

Objectives. — The  first  great  object  of  the  experimental  method  is  to  determine  the 
relationship  by  descent  of  the  species  and  variads  already  in  existence.  In  doing  this 
it  necessarily  deals  with  the  production  of  new  variads  under  known  conditions,  and 
this  leads  to  the  study  of  the  whole  question  of  the  causes  and  methods  by  which  new 
forms  arise.  The  latter  opens  up  the  fundamental  problems  of  the  origin  and  trans- 
mission of  new  characters,  the  solution  of  which  is  possible  only  through  the  widest 
range  of  experiments  under  measured  conditions.  In  close  relation  to  the  origin  of  forms 
stands  the  experimental  study  of  the  criteria  employed  to  distinguish  variads,  species, 
and  genera.  This  is  of  particular  value  to  existing  taxonomy,  and  hence  is  one  of  the 
first  as  well  as  one  of  the  easiest  points  of  attack.     In  this  the  correlation  that  exists 


INTRODUCTION.  23 

between  organs  or  parts  offers  one  of  the  most  promising  of  objectives  and  one  that  may 
serve  to  explain  structures  whose  origin  is  now  entirely  obscure.  It  seems  probable 
that  the  correlation  between  parts  is  at  bottom  chiefly  a  question  of  competition  for  food, 
and,  if  this  be  true,  the  widest  experimental  vista  is  opened.  While  any  of  these 
problems  may  serve  as  the  entry  to  experimental  evolution,  they  are  all  so  interrelated 
that  a  comprehensive  attack  upon  them  alone  promises  to  yield  adequate  results  in  a 
reasonable  time. 

Variads. — The  ecological  attack  upon  the  problems  of  evolution  has  led  to  the  emphasis 
of  three  fundamental  points,  namely,  origin,  fixation,  and  differentiation.  It  proceeds 
upon  the  certain  knowledge  that  new  forms  of  plants  are  constantly  being  produced 
by  the  impact  of  environment,  and  hence  its  first  task  is  to  analyze  the  various  methods 
of  origin  (Clements,  1907,  1908).  Further  studies  of  origin  at  the  Alpine  Laboratory 
have  confirmed  the  hypothesis  that  direct  adaptation  to  the  habitat  has  there  produced 
the  largest  number  of  new  forms  of  plastic  species.  Mutation  now  seems  less  important 
than  it  did  15  years  ago,  but  this  is  partly  due  to  the  increasing  difficulty  of  distinguishing 
mutants  from  variants,  and  sometimes  even  from  ecads.  Much  of  variation  is  undoubt- 
edly response  to  the  gradual  change  of  an  efficient  factor,  or  to  minute  habitats  of  varying 
intensity.  Further  search  has  not  increased  the  small  number  of  probable  hybrids,  and 
it  has  become  necessary  to  attempt  the  direct  production  of  hybrids  in  nature.  In 
spite  of  the  changing  importance  of  the  methods  of  origin,  it  still  appears  certain  that 
adaptation,  mutation,  variation,  and  hybridization  comprise  the  four  processes  of 
evolution,  though  it  now  seems  evident  that  adaptation  and  hybridization  constitute 
the  two  basic  modes.  The  resulting  differentiations  of  the  species  are  distinguished 
as  ecads,  mutants,  variants,  and  hybrids,  and  are  included  under  the  general  term 
variad.  As  to  fixation  of  these,  evidence  is  slowly  accumulating  to  show  that  this  may 
be  cumulative,  and  that  even  ecads  may  run  the  whole  gamut  of  constancy  from  the 
most  inconstant  to  the  most  fixed.  Moreover,  one  character,  such  as  form,  may  become 
fixed,  while  another  arising  from  the  same  factor,  such  as  the  time  of  blooming,  may  be 
unstable.  Finally,  it  seems  clear  to  the  ecologist  that  degree  of  differentiation  must 
come  to  play  a  more  definite  role  in  the  question  of  species  and  variads,  and  that  this 
can  be  attained  only  through  objective  measurement. 

METHODS  OF  TREATMENT. 

General  plan. — On  the  basis  of  the  principles  discussed  above,  a  series  of  monographs 
is  planned  to  comprise  a  large  number  of  the  most  important  genera  and  families  of 
North  America.  For  a  number  of  reasons  the  interest  centers  in  the  West,  chiefly  because 
this  still  affords  the  fullest  opportunity  for  the  application  of  statistical  and  experimental 
methods  on  a  large  scale.  It  provides  a  much  greater  range  of  climatic  and  edaphic 
conditions,  and  to  this  appears  to  be  related  a  correspondingly  greater  evolutionary 
activity.  A  further  reason  of  the  greatest  importance  hes  in  the  fact  that  the  four 
bases  for  ecological  research,  namely.  Pike's  Peak,  Tucson,  Berkeley,  and  Lincoln, 
afford  unique  opportunity  for  applying  the  phylogenetic  method  in  the  midst  of  the 
great  cHmates  and  climaxes  of  the  West.  Finally,  the  vegetation  of  the  West  is  not 
only  of  the  first  importance  in  relation  to  forestry,  grazing,  agriculture,  land  classification, 
and  utilization,  but  it  probably  also  furnishes  the  best  opportunity  in  the  world  for  the 
comprehensive  and  fundamental  development  of  the  science  of  vegetation  itself  in  relation 
to  cUmate  and  soil. 

The  three  genera  treated  in  this  monograph  were  selected  because  of  their  taxonomic 
and  ecologic  interest.  They  have  been  objects  of  the  most  active  evolution,  with  which 
has  gone  the  widest  distribution,  both  as  to  cUmate  and  soil.  Ecologically,  they  are 
unsurpassed  in  the  number  of  dominants  and  subdominants  they  furnish  to  the  vegeta- 


24  THE    PHYLOGENETIC   METHOD    IN   TAXONOMY. 

tion.  As  a  consequence,  they  constitute  indicators  of  great  value,  especially  with  refer- 
ence to  alkaline  soils.  Economically,  the  chief  importance  of  Artemisia  and  Atriplex 
is  as  browse  plants,  while  Chrysothamnus  is  interesting  as  a  source  of  native  rubber. 
All  three  genera  have  yielded  a  large  number  of  segregates,  and  hence  afford  a  good 
test  of  the  phylogenetic  method  in  taxonomy  and  of  its  value  in  actual  use.  Conse- 
quently, while  the  treatment  has  been  made  as  thorough  and  consistent  as  possible, 
much  thought  has  been  given  to  rendering  the  results  of  the  greatest  usefulness  to  the 
non-specialist,  ranging  from  the  botanist  and  forester  at  one  end  to  the  physician  and 
plant-lover  at  the  other. 

Field  work. — As  already  indicated,  taxqnomic  studies  can  be  prosecuted  to  the  best 
advantage  in  places  where  the  plants  grow  under  natural  conditions.  It  is  only  by  this 
means  that  a  sufficiently  large  number  of  individuals  can  be  passed  in  review,  their  varia- 
tions noted,  and  the  proper  correlations  made  with  environmental  conditions.  Other 
methods  have  certain  advantages ;  for  example,  garden  cultures  permit  of  the  assembling 
of  forms  for  comparison  and  experimentation,  but  the  time  is  past  when  any  considerable 
number  of  North  American  or  European  plants  should  be  described  as  new  or  opinions 
ventured  as  to  their  proper  classification  without  a  first-hand  knowledge  of  their  behavior 
in  the  field.  The  value  of  careful  studies  in  garden  and  herbarium  should  not  be  mini- 
mized. In  the  case  of  a  few  rare  species  no  other  method  is  at  present  available,  but  the 
comparatively  small  number  of  specimens  that  can  be  assembled  even  in  the  largest 
establishments  renders  the  results  of  such  work  necessarily  incomplete.  It  seems, 
therefore,  that  greater  efforts  should  be  made  by  taxonomists  to  carry  more  of  their 
work  into  the  field  and  that  much  better  facilities  should  be  provided  for  such  investi- 
gations. 

With  this  importance  of  direct  field  studies  in  mind,  much  time  has  been  given  to  them 
in  the  preparation  of  the  present  monographs.  A  general  ecologic  and  taxonomic  interest 
in  the  genera  here  treated  had  resulted  in  the  assembling  of  a  considerable  number  of 
data  before  intensive  work  was  begun.  The  earliest  field  trip  with  these  groups  espe- 
cially in  mind  was  in  1917.  In  August  of  that  year.  Hall  made  collections  and  studies 
of  Chrysothamnus  in  Colorado,  Wyoming,  and  Nevada  and  spent  the  remaining  months 
of  the  year  largely  upon  this  genus,  about  six  weeks  being  given  to  field  studies  in  eastern 
California  and  Nevada.  These  were  continued  in  January  and  February  of  1918, 
during  which  months  much  distributional  and  ecologic  information  was  obtained  in 
the  desert  area.  In  May,  1918,  Clements  prosecuted  field  studies  on  all  three  genera 
as  they  occur  between  Tucson,  Arizona,  and  Berkeley,  California,  and  was  joined  by 
Hall  in  June  for  similar  investigations  on  a  motor  trip  extending  into  Oregon  and  thence 
to  Colorado.  In  the  late  summer,  Clements  worked  south  to  Texas  and  west  to  Arizona, 
while  Hall  studied  in  western  Colorado,  Utah,  and  Nevada.  The  latter  also  visited 
eastern  California,  and  in  December  worked  from  Reno,  Nevada,  to  San  Diego,  the 
interest  centering  chiefly  on  Chrysothamnus.  General  field  studies  were  combined  with 
experimental  activities  in  Mono  County,  California.  Some  of  the  results,  especially 
those  bearing  upon  the  possibiUties  of  this  genus  as  a  source  of  rubber  and  a  classification 
of  the  forms  of  C.  nauseosus,  together  with  data  secured  in  Utah  by  M.  E.  Jones  and  in 
Oregon,  Cahfornia,  and  Nevada  by  E.  C.  McCarty  and  J.  R.  Bruff,  have  been  published 
by  Hall  and  Goodspeed  (1919). 

The  summer  of  1919  was  again  spent  by  both  authors  at  the  Alpine  Laboratory  on 
Pike's  Peak,  Colorado,  and  collections  were  made  from  adjacent  districts.  At  the  close 
of  the  summer's  work,  field  studies  were  prosecuted  in  unison  during  an  automobile 
trip  from  the  Laboratory  to  Wyoming  and  across  Utah  and  Idaho  to  Oregon  and  Cali- 
fornia, Clements  continuing  the  work  to  Tucson,  Arizona.  In  1920,  Clements  worked 
along  a  different  route  between  Tucson  and  Berkeley  and  made  a  trip  from  Arizona  to 


rary 


INTRODUCTION.  25 

Nebraska  and  Colorado,  where  the  summer  was  spent  at  the  Alpine  Laboratory,  except 
for  an  ecologic  and  taxonomic  excursion  into  the  Bad  Lands  of  Wyoming,  South  Dakota, 
and  Nebraska.  In  the  meantime.  Hall  prosecuted  studies,  especially  on  Atriplex,  in 
the  alkaline  districts  of  Utah,  Colorado,  and  neighboring  States.  In  the  late  summer  a 
joint  motor  trip,  with  numerous  stops  and  short  sidetrips,  extended  across  southern 
Colorado  and  northern  New  Mexico  to  Arizona,  Hall  continuing  to  the  borders  of 
Lower  California. 

In  1921,  Clements  again  motored  from  Arizona  to  Nebraska  and  the  Alpine  Laboratory, 
continuing  in  August  to  the  Pacific  Coast.  Hall  spent  a  month  in  August  and  September 
in  the  mountainous  portions  of  Idaho,  Montana,  and  Washington,  and  then  joined 
Clements  for  field  work  in  eastern  Oregon,  western  Nevada,  and  eastern  California, 
going  as  far  south  as  Mono  County.  Later  in  the  year  studies  were  made  on  the  Arte- 
misias  of  the  coastal  slope  of  California  and  on  the  Atriplexes  of  the  San  Joaquin  Valley, 
the  latter  in  connection  with  Dr.  H.  H.  Severin,  whose  intimate  acquaintance  with  these 
plants  rendered  the  trip  especially  valuable. 

Frequent  short  trips  were  made  in  addition  to  those  outlined  above,  these  being 
mostly  confined  to  Arizona,  California,  and  Colorado.  Short  stops  were  also  made  at 
numerous  railroad  stations  when  traveling  by  train.  Most  of  these  were  between  the 
Pacific  Coast  and  Colorado,  but  a  few  were  on  the  Atlantic  seaboard.  Because  of  the 
interest  in  phylogeny,  an  endeavor  was  made  to  reach  all  stations  in  the  West  where  the 
genera  occurred  in  abundance  and  where  information  regarding  variations  and  inter- 
mediate forms  could  be  obtained.  Type  locahties  were  also  visited  as  far  as  possible  and 
data  secured  with  a  view  to  determining  the  degree  of  constancy  in  the  characters  used 
as  a  basis  for  species  and  varieties  previously  proposed  by  others.  It  is  with  deep 
regret  that,  because  of  lack  of  time  and  facilities,  it  has  been  found  impossible  to  carry  the 
field  work  into  Canada  and  the  Arctic  regions  on  the  one  hand  and  into  Mexico  on  the 
other. 

Results  of  statistical  studies  and  experiments. — Taxonomic  botany  is  sadly  in  need  of 
more  exact  methods  of  investigation.  Far  too  many  opinions  have  been  expressed,  too 
many  species  proposed,  and  too  many  descriptions  drawn  after  a  casual  examination  of 
only  a  few  specimens,  and  sometimes  without  subjecting  these  to  accurate  measurements. 
During  the  present  studies  much  time  and  thought  has  been  given  to  an  attempt  to 
remedy  this  condition.  Consequently,  all  criteria  used  have  been  subjected  to  the 
quantitative  test  as  far  as  possible.  Sometimes  the  results  are  expressed  in  tabular  form, 
since  this  affords  a  concise  method  for  the  presentation  of  the  evidence  upon  which  con- 
clusions are  based,  but  in  many  cases  it  has  been  considered  sufficient  to  preserve  the 
data  only  in  the  herbarium  and  thus  conserve  space.  It  has  been  discovered  by  the  use 
of  these  methods  that  many  criteria  heretofore  supposed  to  be  valid  break  down  com- 
pletely, whereas  others  commonly  overlooked  are  shown  to  possess  real  merit.  A  notable 
example  of  this  latter  condition  is  the  case  of  relation  of  length  of  stylar  appendage 
to  total  length  of  style-branch  in  Chrysothamnus.  By  reference  to  table  23  it  will  be 
seen  that  this  character  is  too  variable  for  use  in  separating  most  of  the  subspecies  of 
C.  nauseosus,  but,  on  the  other  hand,  that  two  of  these  are  set  off  from  the  others  and 
brought  near  to  each  other  on  the  basis  of  this  trait.  The  results  are  useful  not  only 
for  diagnostic  purposes,  but,  what  is  of  more  importance,  as  indicating  the  relationships 
of  the  forms  involved. 

The  next  step  in  the  application  of  the  statistical  method  will  be  the  expression  of 
results  by  the  use  of  graphs,  as  is  commonly  done  by  biometricians.  This  seems  unneces- 
sary in  the  present  work,  since  the  results  can  be  read  directly  from  the  tables  with  almost 
as  great  ease  as  when  expressed  graphically.  The  importance  of  quantitative  methods 
and  the  use  of  graphs  has  been  emphasized  recently  by  MacLeod  (1919). 


26  THE    PHYLOGENETIC   METHOD    IN   TAXONOMY. 

The  value  of  all  quantitative  studies  depends  upon  the  accuracy  of  the  methods 
employed.  All  measurements  and  counts  tabulated  in  this  paper  were  made  either  by 
one  of  the  authors  or  by  a  trained  assistant.  In  the  latter  case  a  portion  of  the  results 
indicated  for  each  form  were  carefully  checked  and  all  doubtful  or  extreme  results  were 
either  verified  or  eliminated.  The  examinations  were  carried  out  with  the  aid  of  binocular 
dissecting  microscopes  equipped  with  micrometer  disks  ruled  to  0. 1  mm.  Larger  measure- 
ments, such  as  dimensions  of  the  larger  involucres,  were  made  by  using  fine-pointed 
calipers  with  a  set-screw  attachment.  The  dimensions  are  for  material  preserved  in 
liquid,  or,  when  this  was  not  available,  for  dried  material  which  had  been  boiled  after 
the  usual  manner.  It  is  believed  that  the  only  serious  source  of  error  is  in  the  number 
of  disk-flowers  reported  for  the  Artemisias.  In  these  plants  the  central  flowers  some- 
times mature  and  drop  out  in  the  process  of  pressing.  Therefore  counts  made  from 
herbarium  specimens  may  be  too  low  in  some  instances.  Wherever  this  was  suspected 
the  space  in  the  table  was  left  blank.  The  importance  of  boiling  before  taking  measure- 
ments of  dried  organs  should  be  emphasized  when  a  high  degree  of  accuracy  is  desired. 
In  the  Compositae  the  heads  increase  their  diameter  on  pressing  by  as  high  as  25  per  cent 
in  some  cases  and  the  flowers  are  sometimes  appreciably  shortened  by  drying  and 
wrinkling.  The  original  shape  and  size  are  almost  exactly  regained  by  immersing  in 
boiling  water  for  a  few  seconds. 

A  series  of  experiments  has  been  instituted  for  the  purpose  of  testing  the  nature  of 
some  of  the  criteria  used  in  the  classification  of  the  genera  here  treated.  Since  the  plants 
are  nearly  all  perennial,  the  results  now  available  are  limited.  Transplants  of  Chryso- 
thamnus  have  been  carried  from  the  desert  area  and  established  in  coastal  districts, 
while  others  have  been  moved  into  different  habitats  in  the  Great  Basin,  with  the  result 
that  some  definite  information  has  been  secured  as  to  the  constancy  of  certain  forms. 
Experiments  in  pruning  and  in  the  cutting  of  roots  at  diflFerent  depths  have  supplied 
data  as  to  the  ecologic  behavior  of  this  genus  of  plants.  Reciprocal  transplants  of  peren- 
nial Artemisias  in  Colorado  have  demonstrated  the  constancy  of  such  characters  as 
amount  of  pubescence  for  a  period  of  three  years  in  some  cases,  but  it  is  still  too  early 
to  predict  final  results.  Some  of  the  annual  Atriplexes  have  been  grown  at  Berkeley, 
where  they  could  be  kept  under  observation,  with  the  result  that  certain  characters  of 
young  plants,  particularly  leaf  position,  have  been  found  to  be  so  different  from  those 
described  by  earlier  students  of  the  genus  that  fundamental  changes  in  the  classification 
have  been  necessary.  The  final  results  of  the  experimental  studies  will  be  reported 
subsequently. 

Illitslrations. — All  of  the  accepted  species  and  many  of  the  subspecies  and  minor  forms 
are  illustrated  in  the  plates  which  accompany  this  memoir.  This  is  entirely  the  work  of 
Miss  Ruth  Jeannette  Powell,  to  whom  the  authors  are  under  lasting  obligations  for  the 
exercise  of  much  patience  as  well  as  artistic  ability.  Extensive  scientific  training  has 
given  her  an  insight  into  the  methods  and  aims  of  botanical  research  which  has  greatly 
added  to  the  accuracy  of  the  results  and  to  the  clearness  of  their  expression. 

A  majority  of  the  plates  were  prepared  from  fresh  specimens  sent  directly  from  the 
field.  When  it  was  found  necessary  to  resort  to  dried  or  herbarium  material,  this  was 
first  restored  to  its  natural  form  by  immersing  in  boiling  water  for  a  few  seconds,  or  at 
least  a  small  portion  was  so  treated  to  secure  a  correct  idea  of  the  size,  shape,  and  relative 
position  of  the  various  parts.  In  some  Artemisias  the  difference  between  fresh  and  dried 
heads  amounts  to  as  much  as  10  per  cent,  but  this  varies  with  the  amount  of  shrinking 
and  wrinkling.  All  drawings  made  from  dry  specimens  are  indicated  in  the  explanations 
accompanying  the  plates,  and  all  such  were  prepared  from  boiled  material.  The  amount 
of  enlargement  or  reduction  of  each  drawing  is  also  indicated.  It  will  be  noted  that 
this  has  been  kept  constant  for  each  structure  throughout  a  genus,  thus  enabling  one 


INTRODUCTION.  27 

to  make  direct  comparisons  between  the  difTerent  forms  without  resorting  to  computa- 
tions. The  only  features  not  drawn  to  scale  are  the  thumb  sketches  sometimes  inserted 
to  indicate  habit.  These  were  prepared  for  some  species  after  studies  had  been  made 
by  the  artist  in  the  field;  most  of  them,  however,  were  constructed  from  photographs 
of  living  plants  taken  for  the  purpose. 

All  of  the  drawings,  with  the  exception  of  the  thumb  sketches  just  mentioned,  are 
believed  to  be  accurate  as  to  shape  and  size.  The  smaller  details  were  drawn  as  they 
appear  under  the  binocular  dissecting  microscope,  and  measurements  were  made  with 
the  aid  of  a  micrometer  disk.  In  all  cases  a  subsequent  examination  was  made  to  be 
certain  that  the  dimensions  adopted  represented  the  average  of  the  material  in  hand. 

Phylogenetic  charts. — Since  one  of  the  main  objects  of  the  present  monographs  is  to 
present  a  classification  based  upon  phylogeny,  it  has  been  thought  desirable  to  give  a 
graphic  presentation  of  the  relationships  between  the  numerous  forms.  A  number  of 
charts  has  been  prepared  to  accompany  the  discussions  of  phylogeny.  There  is  no 
thought  of  finality  in  the  diagrams  as  here  presented.  Their  purpose  is  to  express 
the  results  of  evolution  as  now  understood,  and  it  is  fully  appreciated  that  the  evidence 
for  certain  phyletic  lines  is  still  far  from  conclusive.  However,  the  importance  of  natural 
groupings  and  their  expression  in  a  readily  intelligible  form  is  so  great  that  the  charts 
are  here  presented  as  a  contribution  to  the  general  subject  of  phylogeny.  Moreover,  in 
some  groups  the  relationships  are  so  well  understood  that  only  slight  modifications  will 
be  necessary  as  the  result  of  further  studies. 

Many  of  the  charts  are  to  be  looked  upon  as  expressions  of  degree  of  relationship 
rather  than  as  illustrating  definite  lines  of  evolution.  This  is  because  it  is  sometimes 
easier  to  make  out  the  relationships  of  biologic  forms  than  it  is  to  demonstrate  the  lines 
along  which  they  have  evolved.  This  is  particularly  true  as  regards  the  direction  of 
evolution.  For  example,  in  many  of  the  charts  the  relationships  of  certain  groups  are 
pretty  well  understood,  but  it  is  at  present  impossible  to  determine  which  one  represents 
the  original  stock.  Therefore,  it  may  be  necessary  in  some  cases  to  start  with  one  of 
the  forms  here  placed  fairly  well  up  in  the  scheme,  proceed  thence  towards  the  lower  ones, 
and  then  around  to  other  branches  leading  to  the  most  highly  developed  of  all. 

Even  though  the  exact  lines  of  evolution  can  not  always  be  indicated  with  certainty, 
the  bringing  together  of  related  forms  into  increasingly  larger  and  larger  natural  groups 
should  be  undertaken  wherever  possible,  for  this  is  the  basis  of  taxonomy.  The  graphic 
representation  of  such  relationships,  if  carried  to  all  groups  of  plants,  would  doubtless 
be  of  much  value  to  geneticists,  breeders,  and  others  who  need  to  know  the  related  forms 
of  plants  with  which  they  are  working.  Furthermore,  if  properly  prepared,  phylo- 
genetic charts  may  replace,  to  some  extent  at  least,  the  analytical  keys  now  in  vogue. 
Largely  with  this  use  in  mind,  the  differentiating  characters  as  well  as  the  names  of  the 
groups  themselves  have  been  inserted  on  the  charts  here  presented. 

Citation  of  authors,  synonyms,  and  specimens. — The  almost  universal  custom  of  fol- 
lowing the  specific,  subspecific,  and  varietal  name  by  that  of  the  author  who  first  used 
it  is  followed  throughout  this  monograph.  It  is  hoped,  however,  that  as  names  and 
combinations  of  names  become  established,  this  practice  will  be  deemed  unnecessary, 
since  its  object  is  accuracy  in  the  application  of  terms  rather  than  credit  to  the  author. 
When  new  combinations  are  made  for  the  first  time  in  this  work,  the  first  author  of  the 
final  term  is  cited  in  parenthesis.  There  is  no  important  reason  why  this  should  be 
followed  by  the  name  of  the  author  of  the  new  combination,  but  as  a  concession  to 
custom  this  is  done  when  such  combination  has  been  made  prior  to  the  issuance  of  this 
volume.  It  therefore  follows  that  the  present  authors  are  responsible  for  all  those  com- 
binations in  which  the  parenthesis  is  not  followed  by  the  name  of  some  other  worker. 
In  the  case  of  a  few  trinomials  the  combination  itself  is  not  new,  but  the  rank  has  been 


28  THE    PHYLOGENETIC   METHOD    IN   TAXONOMY. 

changed,  usually  from  that  of  variety  to  that  of  subspecies.  In  these  instances  the 
carrying  over  of  the  author  of  the  variety  as  the  author  also  of  the  subspecies  is  con- 
sidered not  justifiable. 

An  attempt  has  been  made  to  give  a  complete  synonymy  under  each  of  the  species, 
except  when  the  synonym  applies  only  to  foreign  variations,  when  its  application  to 
North  American  forms  can  not  be  made  with  certainty,  or  when  it  results  from  such 
remote  transfers  as  that  of  Chrysothamnus  from  Aster. 

The  citation  of  specimens  examined  is  given  for  two  principal  purposes:  (1)  to  indi- 
cate the  distribution,  and  (2)  to  enable  workers  at  the  various  herbaria  to  gain  a  clear 
notion  of  the  authors'  concepts  of  the  species,  subspecies,  and  minor  variations.  Speci- 
mens fairly  representative  of  the  group  under  consideration  and  from  different  portions 
of  the  area  of  distribution  have  therefore  been  chosen  for  citation,  or  if  not  representa- 
tive, the  variation  is  then  indicated  in  parenthesis.  A  complete  citation  of  all  specimens 
examined  is  given  only  when  the  group  is  rare  or  otherwise  of  special  interest.  Initials 
and  titles  of  collectors  are  seldom  given,  since  it  is  believed  that  their  omission  will  not 
lead  to  confusion  when  looking  up  the  specimens  in  herbaria.  The  names  of  certain 
collectors  have  become  so  closely  associated  with  botanical  work  in  special  regions  that 
their  initials  seem  superfluous.  When  collections  by  another  with  the  same  surname 
are  cited,  the  initials  of  this  latter  botanist  are  given.  Thus,  "Jones"  refers  to  Marcus 
E.  Jones,  for  plants  gathered  anywhere  in  the  West,  the  few  collections  by  W.  W. 
Jones  being  so  cited;  "Nelson"  refers  to  Aven  Nelson  when  Rocky  Mountain  plants  are 
indicated,  but  to  "E.  W.  Nelson"  in  the  case  of  Mexican  specimens,  collections  by 
Elias  Nelson  being  cited  in  full. 

The  names  of  the  herbaria  in  which  the  cited  specimens  were  seen  are  indicated  by 
abbreviations  in  parenthesis  following  the  name  of  the  collector.  The  abbreviations 
adopted  are  the  following: 

CI,  Unmounted  specimens  provisionally  retained  by  the  authors  as  part  of  the  working  collection  of  the  Carnegie 
Institution. 

DS,      Dudley  Herbarium  of  Stanford  University. 

Gr,       Gray  Herbarium  of  Harvard  University. 

NY,  Herbarium  of  the  New  York  Botanical  Garden,  including  the  Torrey  and  other  herbaria  of  Columbia  Uni- 
versity, there  on  deposit. 

Phila,  Herbarium  of  the  Academy  of  Natural  Sciences  of  Philadelphia. 

R,         Rocky  Mountain  Herbarium  of  the  University  of  Wyoming. 

SF,       Herbarium  of  the  Cahfomia  Academy  of  Sciences,  San  Francisco. 

UC,      Herbarium  of  the  University  of  California,  including  the  Brandegee  Herbarium. 

US,      United  States  National  Herbarium,  including  that  of  the  United  States  Department  of  Agriculture. 

Herbaria  studied  and  acknowledgments. — The  detailed  herbarium  and  statistical  studies 
necessary  as  supplementing  the  field  work  have  been  carried  out  for  the  most  part  at 
the  University  of  California.  Here  every  facility  was  freely  available,  including  the  use 
of  the  herbarium  and  botanical  library,  and  grateful  acknowledgment  is  made  to  the 
University  authorities  and  especially  to  the  Department  of  Botany.  Other  California 
herbaria  studied  include  those  of  the  California  Academy  of  Sciences,  the  Dudley 
Herbarium  of  Stanford  University,  and  the  C.  F.  Baker  Herbarium  of  Pomona  College. 
The  Rocky  Mountain  Herbarium,  at  the  University  of  Wyoming,  was  visited  a  number 
of  times  and  found  to  be  extremely  helpful,  especially  because  of  the  large  amount  of 
critical  material  brought  together  by  President  Aven  Nelson  and  his  staff.  Professor 
Marcus  E.  Jones,  of  Salt  Lake  City,  courteously  aided  in  the  study  of  types  and  other 
critical  material  in  his  collection,  and  the  herbaria  at  the  Universities  of  Nevada  and 
Arizona  were  frequently  consulted.  All  of  the  material  belonging  to  the  three  genera 
here  treated  was  examined  by  both  authors  in  the  winter  of  1920-21  at  three  leading 
herbaria  on  the  Atlantic  Coast,  namely,  the  Gray  Herbarium  of  Harvard  University, 
especially  rich  in  types  and  in  specimens  gathered  on  the  early  surveys  and  expeditions 


INTRODUCTION.  29 

and  well  supplemented  by  more  recent  collections,  especially  by  Professor  Merritt  L. 
Fernald  and  his  colleagues  from  the  northeast  coast;  the  Herbarium  of  the  New  York 
Botanical  Garden,  where  a  splendid  collection  of  Artemisias  has  been  assembled,  largely 
through  the  efforts  of  Dr.  P.  A.  Rydberg  during  the  preparation  of  his  account  of  this 
genus  for  the  North  American  Flora,  and  where  the  Torrey  and  other  herbaria  of  Colum- 
bia University  are  deposited;  and  the  United  States  National  Herbarium,  where  the 
series  of  Atriplex  is  especially  noteworthy,  the  original  collection  having  been  much 
enlarged  by  Mr.  Paul  C.  Standley  during  his  preparation  of  a  revision  of  the  species  for 
the  North  American  Flora.  The  Academy  of  Natural  Sciences  of  Philadelphia  was 
visited  with  special  reference  to  the  types  of  Nuttall's  species.  Critical  studies  were 
made  at  the  E.  L.  Greene  Herbarium,  now  at  the  University  of  Notre  Dame,  South 
Bend,  Indiana,  and  photographs  taken  of  many  of  the  type  specimens.  The  herbarium 
of  the  Missouri  Botanical  Garden  was  consulted  in  regard  to  certain  types  and  duplicate 
types  there  deposited,  but  time  did  not  permit  of  a  complete  examination  of  all  the 
specimens  in  this  rich  collection. 

It  has  been  found  desirable  in  a  few  cases  to  borrow  material  for  critical  study  at 
Berkeley.  Thus,  a  considerable  collection  of  Chrysothainnus  was  received  on  loan  from 
the  Rocky  Mountain  Herbarium  through  the  courtesy  of  President  Aven  Nelson,  and 
Dr.  B.  L.  Robinson  has  kindly  sent  specimens  of  Atriplex  and  Artemisia  from  the  Gray 
Herbarium  of  Harvard  University.  An  authentic  specimen  of  Artemisia  domingensis 
was  contributed  by  the  Botanical  Garden  and  Museum  of  Berlin,  Germany,  at  the 
suggestion  of  Dr.  I.  Urban.  Photographs  of  types  have  proved  exceedingly  useful, 
especially  when  accompanied  by  fragments  of  the  specimens  themselves.  Such  photo- 
graphs were  secured  in  large  numbers  from  the  United  States  National  Herbarium,  the 
New  York  Botanical  Garden,  the  Gray  Herbarium,  and  the  Greene  Herbarium.  These 
prints,  together  with  the  fragments  which  usually  accompanied  them,  were  obtained  in 
part  as  an  exchange  with  the  University  of  California,  where  they  now  form  a  part  of 
the  botanical  collection. 

Grateful  acknowledgment  is  here  made  to  the  curators  of  the  various  herbaria  men- 
tioned above,  both  for  the  privilege  of  examining  specimens  under  their  care  and  for 
valuable  suggestions  and  critical  opinions  given  during  the  progress  of  the  work.  In 
this  latter  connection  should  be  mentioned  also  the  large  number  of  botanists,  foresters, 
and  others  who  have  been  consulted  from  time  to  time  on  certain  matters  with  which 
they  were  especially  familiar. 


30 


THE    PHYLOGENETIC   METHOD    IN    TAXONOMY. 


REFERENCES. 


Babcock,  E. 


and  R.  E.  Clausen.     1918.     Genetics 

in  relation  to  agriculture. 
Bateson,  W.     1913.     Mendel's  principles  of  heredity. 

.     1913.'     Problems  in  genetics.     Page  259. 

Bentham,  G.,  and  J.  D.  Hookeb.     1862-1883.     Genera 

plantarum. 
Besset,  C.  E.     1896.     Essentials  of  botany. 
.     1897.     The   phylogeny   and    taxonomy   of   An- 

giosperms.     Bot.  Gaz.  24  :  1. 

.     1912.     Outlines  of  plant  phyla.     3d  ed. 

.     1915.     The  phylogenetic  treatment  of  flowering 

plants.     Ann.  Mo.  Bot.  Card.  2  :  109. 
Bonnieb,   G.     1890.     Cultures   expirimentales   dans    les 

Alpes  et  les  Pyr^n^es.    Rev.  Gen.  Bot.  2:  514. 
.     1895.     Recherches  eip6rimentales  sur  I'adapta- 

tion  des  plantes  au  climat  alpin.     Ann.     Sci. 

Nat.  7  :  20  :  218. 
.     1920.     Sur  le  changements,  obtenues  eipferimen- 

talement,  dans  les  formes  vfegttales.     Comp. 

Rend.  170  :  1356;  Bot.  Abs.  8  :  32. 
Chase,  A.     1921.     The  Lipnaean  concept  of  pearl  millet. 

Amer.  Jour.  Bot.  8  :  41. 
Clausen,  J.      1922.      Studies   on   the   collective   species 

Viola  tricolor  L.     Bot.  Tids.  37  :  363. 
Clements,  F.  E.     1902.     Greek  and  Latin  in  biological 

nomenclature.     Univ.  Nebr.  Studies  3:1. 
.     1904.     Development   and   structure   of   vegeta- 
tion.    Rep.  Bot.  Surv.  Nebr.  7  :  68. 
.     1905.     Research  methods  in  ecology.     Pages  12, 

145. 

.     J907.     Plant  physiology  and  ecology.     Page  185. 

.     1907.'     The  origin  of  new  forms  by  adaptation. 

Science  25  :  287. 
.     1908.     An  ecologic  view  of  the  species  question. 

Amer.  Nat.  42  :  253. 
,  and  E.  S.  Clements.     1913.     Rocky  Mountain 

flowers. 
,  and  H.  M.  Hall.     1918.     Reciprocal   transplants. 

Year  Book  Carnegie  Inst.  Wash.  17  :  292. 
Field  and  garden  study  of  genera  and  species. 

lb.,  294. 
. •     1919.     Experimental    taxonomy.     lb., 

18  :  334. 

Field  and  garden  study  of  genera  and  species. 
lb.,  335. 
1    .     1920.     Experimental    taxonomy.     lb., 

19  :  345. 

Taxonomic  monographs.     76.,  346. 
.    .     1921.     Experimental     taxonomy.     lb., 

20  :  395. 

,        The  phylogenetic  method  in  taxonomy.     lb., 

396. 
Coulter,  J.   M.     1885.     Manual  of  the  botany  of  the 

Rocky  Mountain  region. 
,    and  A.  Nelson,     1909.     New  manual  of  botany 

of  the  central  Rocky  Mountains. 


DeCandolle,  A.  P.  1819.  Th^orie  *16mentaire  de  la 
botanique  ou  exposition  des  principes  de  la 
classification  naturelle  et  de  I'art  de  decrire 
et  d'^tudier  des  v^gfitaux.     3d  ed.     1844. 

Eichler,  a.  W.  1876.  Syllabus  der  Vorlesungen  Qber 
Phanerogamenkunde. 

.     1880.     Syllabus  der  Vorlesungen  iiber  specielle 

und  medicinisch-pharmaceutische  Botanik 
(2d  ed.  of  above;  3d  ed.  1883;  4th  ed.  1886.) 

Endlicher,  S.  1836-1850.  Genera  plantarum  secundum 
ordines  naturales  disposita. 

Enqler,  a.  1892.  Die  systematische  Anordnung  der 
monokotyledonen  Angiospermen.  Abh.  K6- 
nigl.  Akad.  Wiss.  Berlin.  2. 

.     1892.     Syllabus  der  Vorlesungen  iiber  specielle 

und  medicinisch-pharmaceutische  Botanik. 
Eine  Uebersicht  iiber  das  gesammte  Pflan- 
lensystem  mit  Beriickaichtigung  der  Medici- 
nal und  Nutzpflanzen. 

Febnald,  M.  L.  1900.  Is  Artemisia  stelleriana  a  native 
of  New  England?     Rhodora  2  :  38. 

Gray,  A.  1878,1884.  Synoptical  flora  of  North  America. 
2d  ed.     1886. 

Hall.  H.  M.     1920.     Taxonomy  of  the  Madieae.     Year 
Book  Carnegie  Inst.  Wash.  19  :  347. 
Statistical  studies.     lb.,  348. 

.     1921.     Statistical  studies.     lb.,  20  :  397. 

Taxonomy  of  Haplopappus.     lb.,  398. 

,  and  T.  H.  Goodspeed.     1919.     A  rubber  plant 

survey  of  western  North  America.  Univ. 
Calif.  Pub.  Bot.  7  :  159. 

Jordan,  A.     1873.     Des  especes  vfegfetales  aflSnes. 

Jussieu,  a.  de.     1789.     Genera  plantarum. 

KuNTZE,  O.     1891-1898.     Revisio  generum  plantarum. 

Lindley,  J.     1845.     The  vegetable  kingdom. 

Linnaeus,  C.     1737.     Genera  plantarum. 

.      1738.     Classes  plantarum. 

.     1753.     Species  plantarum. 

LoTSY,  J.  P.     1916.     Evolution  by  means  of  hybridization. 

Luerssen,  C.  1882.  Handbuch  der  systematischen  Bo- 
tanik, 2. 

MacLeod,  J.     1919.     Quantitative  method  in  biology. 

Pennell,  F.  W.  1920.  Scrophulariaceae  of  the  central 
Rocky  Mountain  states.  Contr.  U.  S.  Nat. 
Herb.  20  :  9  :  313. 

Robinson,  B.  L.  1901.  Problems  and  possibilities  of 
systematic  botany.     Science  14  :  1. 

.     1906.     Generic  concept  in  the  classification  of 

flowering  plants.     Science  23  :  81. 

Rydberg,  P.  A.  1917.  Flora  of  the  Rocky  Mountain* 
and  adjacent  plains. 

TURESSON,  G.  1922.  Genotypical  response  of  the  plant 
species  to  the  habitat.     Hereditas  3  :  211. 

WiMMER,  F.  1838.  Aristotele:  Phytologiae  Aristoteli- 
cae  fragmenta.  See  Meyer,  Geachichte  der 
Botanik. 


GENUS  ARTEMISIA. 
RELATIONSHIPS  AND  GENERIC  LIMITS. 

Artemisia  is  a  member  of  the  Anthemideae  or  mayweed  tribe  of  the  Compositae. 
Its  nearest  ally  is  Tanacetum,  from  which  it  differs  by  only  one  constant  technical  char- 
acter, namely,  the  type  of  inflorescence,  although  several  other  characters  are  so  nearly 
constant  as  to  remove  any  thought  of  uniting  the  two. 

The  inflorescence  of  the  heads  in  Arteynisia  is  always  of  the  paniculate  type.  Some- 
times the  panicle  is  reduced  to  a  single  raceme,  but  never  or  rarely  to  a  single  head,  and 
nowhere  in  the  genus  do  we  find  any  approach  to  a  cymose  inflorescence.  Tanacetum, 
on  the  other  hand,  has  a  distinctly  cymose  arrangement  of  the  heads,  and  even  when 
the  head  is  solitary,  as  sometimes  occurs  in  T.  huronense,  T.  bipinnatum,  T.  compadum, 
and  other  species,  this  is  evidently  the  result  of  reduction  from  the  cymose  type  as 
indicated  in  most  cases  by  the  presence  of  cymes  in  other  individuals  of  the  same  species. 

A  second  character  useful  in  the  recognition  of  Artemisia  as  distinct  from  Tanacetum 
is  found  in  the  shape  of  the  anther-tips.  In  the  former  genus  these  are  always  lanceolate 
or  subulate  and  pointed;  in  Tanacetum  they  are  broadly  lanceolate  to  ovate  and  more 
or  less  obtuse,  with  the  single  exception  of  the  recently  discovered  T.  compactum,  of 
western  Nevada,  in  which  species  the  tips  are  subulate  and  acute. 

Although  Artemisia  and  Tanacetum  constitute  two  rather  well-defined  and  natural 
genera,  various  attempts  have  been  made  in  the  literature  to  establish  additional  ones 
by  the  process  of  taxonomic  segregation.  One  of  the  earliest  of  these  attempts  was  by 
Tournefort,  who  in  1700  recognized  Artemisia,  Abrotanum,  and  Absinthium  (Inst.  Rei 
Herb.  1:457-460).  These  proposed  genera  were  based  in  part  upon  floral  characters 
and  hence  they  still  serve  as  subgenera  or  sections  in  many  modern  treatments,  but 
their  full  generic  recognition  is  without  practical  value,  since  each  contains  at  least  a 
few  species  which,  in  all  but  purely  technical  characters,  very  closely  resemble  certain 
species  in  one  of  the  other  groups.  The  other  attempts  to  establish  genera  within 
Artemisia  and  Tanacetum  have  been  based  upon  characters  of  slight  importance,  and 
therefore  the  generic  standing  of  the  resulting  segregates  is  very  insecure.  The  latest 
treatment  of  the  North  American  forms  is  by  Rydberg  (N.  Am.  Fl.  34  :  242-285,  1916). 
Since  this  author  is  inclined  to  the  acceptance  of  genera  on  less  important  characters 
than  those  demanded  by  most  botanists,  it  is  not  surprising  to  find  that  all  of  the  earlier 
proposed  segregates,  except  those  of  Tournefort,  are  here  treated  as  genera  and  three 
new  ones  added.  A  list  of  these,  with  a  tabulation  of  the  principal  characters  used  in 
their  differentiation  is  given  in  table  3,  at  bottom  of  next  page. 

The  following  key  has  been  prepared  in  order  to  bring  out  the  contrasting  characters 
fully.  It  differs  in  some  details  from  the  key  given  by  Rydberg.  According  to  the 
treatment  preferred  here,  the  first  four  "genera"  fall  into  Tanacetum,  the  fifth  stands 
as  Crossostephium  but  confined  to  a  single  Old  World  species,  and  the  last  two  are  referred 
back  to  Artemisia. 

Inflorescence  cymose,  the  cyme  occasionally  reduced  to  a  single  head. 
Anther-tips  lanceolate  or  ovate,  more  or  less  obtuse. 

Corollas  of  the  marginal  flowers  oblique;  pappus  coroniform 1.  Tanacetum. 

Corollas  of  marginal  flowers  not  oblique;  pappus  none. 

Achenes  swelling  and  becoming  gelatinous  in  water;  receptacle  pubescent 2.  Vesicarpa. 

Achenes  neither  swelling  nor  becoming  gelatinous  in  water;  receptacle  glabrous. ...   3.  Sphaeromeria. 

Anther-tips  subulate,  acute 4.  ChamarUmiaia. 

Inflorescence  racemose-paniculate. 

Receptacle  glabrous  or  pubescent  but  never  chaffy-bracted. 

Achenes  and  corollas  glabrous  to  arachnoid,  but  not  villous. 

Pappus  a  lacerate  crown;  ray-flowers  in  2  rows 5.  VTossostephium. 

Pappus  wanting;  ray-flowers  in  1  row  or  wanting 6.  Artemisia. 

Achenes  and  corollas  arachnoid-villous '  •  Picrothamnus. 

Receptacle  chaffy-bracted 8-  ArtemisiasiTum. 


32 


GENUS   ARTEMISIA. 


Although  a  discussion  of  Tanacetum  and  its  three  segregates  does  not  fall  within  the 
province  of  this  paper,  Chamartemisia  is  so  near  Artemisia  that  its  generic  position  should 
be  here  considered.  This  proposed  segregate  of  Tanacetum  has  the  subulate  anther-tips 
of  Artemisia,  but  in  habit,  inflorescence,  receptacle,  and  corollas  it  agrees  with  the 
Sphaeromeria  section  of  Tanacetum.  There  is,  to  be  sure,  no  other  Sphaeromeria  with  a 
pappus,  but  the  genuine  species  of  Tanacetum  have  a  coroniform  pappus.  The  species 
of  Artemisia  are  universally  devoid  of  pappus,  and  moreover,  the  presence  or  absence  of 
pappus  can  not  be  accepted  as  of  generic  value  in  this  case.  It  seems,  therefore,  that 
Chamartemisia  is  much  more  closely  related  to  Tanacetum  than  it  is  to  this  genus,  and 
that  it  may  be  referred  to  Tanacetum,  section  Sphaeromeria,  or  a  new  section  established 
for  it,  since  its  distinguishing  characters  are  not  sufficient  to  sustain  a  new  genus.  The 
inflorescence  in  the  few  specimens  thus  far  collected  is  so  reduced  that  one  can  not  say 
with  certainty  whether  it  is  of  the  paniculate  or  of  the  cymose  type,  but  the  assemblage 
of  other  characters  perhaps  warrants  the  conclusion  that  it  is  the  former. 

Crossostephium,  as  here  delimited,  consists  of  but  a  single  species,  namely  C.  arte- 
misioides  Lessing,  based  upon  Artemisia  chinensis  Vahl,  not  Linnaeus,  a  species  of  the 
Philippine  Islands  and  China.  Gray  had  suggested  that  this  be  reduced  to  Artemisia 
and  that  it  stand  next  to  A.  australis  Lessing,  of  the  Hawaiian  Islands,  and  A.  calif ornica 
Lessing,  of  western  North  America  (Syn.  Fl.  P  :  370,  1884).  Rydberg  has  taken  the 
same  view  of  this  relationship,  but  refers  all  three  of  the  species  just  mentioned  to  the 
genus  Crossostephium.  It  seems  that  both  treatments  are  erroneous,  and  that  it  is  better 
to  restrict  Crossostephium  to  C.  arteviisioides  alone.  This  belief  is  based  upon  a  careful 
examination  of  material,  by  which  it  is  found  that  the  American  and  Hawaiian  species 
referred  to  Crossostephium  are  lacking  in  the  two  essential  features  of  that  genus,  namely, 
the  coroniform  pappus  and  the  double  row  of  ray-flowers.  A  more  detailed  statement 
is  given  in  the  discussion  of  the  relationships  of  A.  calif  ornica  (p.  54). 

The  two  remaining  segregates  of  Artemisia  indicated  in  the  preceding  key  are  based 
each  upon  a  single  character.  Picrothamnus,  with  but  one  species,  A.  spinescens, 
is  an  Artemisia  of  the  section  Dracunculus.    It  was  established  by  Nuttall  (Trans.  Am. 


Table  3.— CAaroc/ers 

of  Artemisia,  related 

genera,  and  segregates. 

Anther-tips. 

Inflorescence. 

Pappus. 

Corolla  of  marginal 
flowers. 

Receptacle. 

Tanacetum  Linnaeus 

Ovate,  obtuse 

Cymose  or  solitary 
by  reduction. 

Coroniform . 

Oblique,  somewhat 
ligulate. 

Naked. 

Vesicarpa  Rydberg' 

Ovate-lanceolate. 

Cymose . 

Wanting. 

Nearly  tubular. 

Pubescent. 

Sphaeromeria  Nuttall 

Ovate, 

"obtusish." 

Cymose  or  solitary. 

Wanting. 

Nearly         tubular, 
slightly  if  at  all 
oblique. 

Naked. 

Chamartemisia  Rydberg'      . 

Subulate. 

Solitary     or     two, 
probably  reduced 

Coroniform . 

Nearly  tubular;  no 
hgules. 

Naked. 

Crossostephium  Lessing' 

Subulate. 

Panicle. 

Coroniform . 

Nearly  tubular;  no 
liguIes;in2rows. 

Essentially 
naked. 

Picrothamnus  Nuttall' 

Subulate . 

Racemose. 

Wanting. 

Short,  2-cleft. 

Naked. 

Lanceolate      or 
subulate. 

Panicled      or      the 
panicle     reduced 

Wanting. 

Tubular,  often 
oblique 

Naked    or 
pubescent. 

and    raceme-like 

or  spike-like. 

Artemisiastrum  Rydberg 

Subulate. 

Panicled. 

Wanting. 

Tubular. 

Chaffy. 

'  Differs  from  all  the  others  in  the  somewhat  utricular  achenes,  the  surface  of  which  becomes  gelatinous  in  water. 

'  Chamartemisia  has  pappus  of  Tanacetum,  corolla  of  Sphaeromeria,  and  anther-tips  of  some  Artemisias. 

'  Crossostephium  as  originally  described  has  only  one  species;  extended  by  Rydberg  to  include  Artemisia  californiea  with 
ray-flowers  in  a  single  row  and  no  pappus  (see  page  54). 

*  Picrothamnus  was  separated  from  Artemisia  on  spiny  habit,  villous  achenes,  and  villous  corollas  (achenes  and  corollas 
glabrous  to  rarely  pubescent  in  Artemisia). 


RELATIONSHIPS   AND    GENERIC   LIMITS.  33 

Phil.  Soc.  II.  7:417,  1841)  and  reduced  to  Artemisia,  section  Dracunculus,  by  D.  C. 
Eaton  (Watson,  Bot.  King's  Expl.  180,  1871),  which  reduction  was  accepted  by  Bentham 
and  Hooker,  Gray,  Hoffmann  (in  Engler  and  Prantl's  Natiirlichenpflanzenfamilien), 
and  by  others.  Recently  it  has  been  revived  by  Rydberg  and  others,  but  without  addi- 
tional substantiating  characters.  Its  most  striking  feature  is  the  villous  pubescence  of 
the  achenes  and  corollas.  This  can  not  be  considered  of  generic  or  even  of  sectional 
value,  since,  aside  from  the  fact  that  such  characters  are  never  of  prime  importance, 
the  recognition  of  Picrothamnus  would  lead  to  claims  for  generic  rank  for  such  species 
as  A.  parishi,  in  which  the  achenes  are  arachnoid-pubescent,  while  the  corollas  remain 
glabrous,  and  which  is  also  of  such  close  natural  relationship  to  Artemisia  tridentata 
that  it  is  here  taken  as  a  subspecies.  The  spinescent  habit  is  not  exactly  dupUcated 
elsewhere  in  the  genus,  but  it  is  approached  in  A.  rigida  and  in  some  forms  of  the  Asiatic 
A.  persica  Besser,  one  of  which,  described  as  variety  subspinescens  (Besser,  Fl.  Orient. 
3:374,  1873),  has  similarly  rigid  branches  that  are  persistent  and  indurated  after  anthesis. 
This  does  not  belong  to  the  same  section  as  spinescens,  but  its  tendency  to  become 
subspinose  indicates  that  the  habit  need  not  exclude  a  form  from  the  genus.  Another 
feature  of  spinescens  is  found  in  the  completely  fused  style-branches.  Since  this  fre- 
quently occurs  also  in  several  species  of  the  section  Dracunculus,  as  discussed  under 
the  heading  of  Criteria,  it  seems  to  be  an  additional  bond  between  Picrothamnus  and 
Artemisia,  especially  when  the  high  evolutionary  position  of  Dracunculus  is  considered. 
Any  other  arrangement  would  necessitate  the  assumption  that  the  fused  character  of 
the  style-branches  was  developed  independently  in  two  widely  separated  groups. 

Finally,  Artemisiastrum ,  which  has  been  proposed  as  a  new  genus  to  include  A.  palmeri 
alone,  is  an  evident  recognition  of  the  importance  of  receptacular  bracts.  While  the 
presence  or  absence  of  these  structures  is  of  much  value  in  the  classification  of  the 
Compositae,  their  occasional  occurrence  in  a  genus  whose  species  are  almost  universally 
devoid  of  them  may  be  looked  upon  as  a  possible  case  of  reversion  rather  than  as  the 
basis  for  a  new  genus.  In  fact,  it  is  not  uncommon  for  certain  of  the  Helenieae  to  exhibit 
chaff  on  the  receptacle  of  species  in  which  it  is  usually  naked,  yet  there  is  no  thought 
of  separating  these  aberrant  forms  even  as  species  (Baeria  chrysostoma,  Chaenactis 
carphoclinia,  etc.).  Since  the  other  characters  of  Artemisiastrum  are  not  fundamentally 
different  from  those  of  other  species  of  the  section  Seriphidium,  the  presence  of  recep- 
tacular chaff  may  be  considered  of  not  more  than  specific  value  in  this  case.  An  attempt 
to  assign  the  same  value  to  a  character  wherever  it  appears,  for  the  sake  of  consistency 
or  otherwise,  would  lead  to  the  creation  even  of  new  tribes  for  A.  palmeri  and  for  the 
occasional  forms  of  Baeria  and  Chaenactis  just  mentioned,  on  the  plea  that  this  character 
is  used  elsewhere  in  the  Compositae  for  the  differentiation  of  tribes. 

From  the  considerations  just  presented  it  seems  impossible  that  Picrothamnus  and 
Artemisiastrum  are  other  than  offshoots  from  the  main  line  of  Artemisia,  and  further- 
more that  each  has  arisen  at  a  different  point.  There  is  no  evidence  to  indicate  that 
either  was  developed  before  the  differentiation  of  other  Artemisias  took  place;  in  other 
words,  that  they  represent  phylogenetic  lines  distinct  from  Artemisia.  Their  defense 
must  rest,  therefore,  upon  the  plea  that  their  differentiating  characters  are  such  as  are 
used  elsewhere  for  generic  distinction,  but  such  treatment  leads  neither  to  stability  nor 
to  an  expression  of  the  facts  of  evolution  and  relationship  as  they  are  now  understood. 
For  these  reasons,  these  proposed  segregates  are  here  again  referred  to  Artemisia. 
Crossostephium  is  an  entirely  different  case.  When  restricted  to  its  single  original  species 
it  represents  a  definite  phylogenetic  hne  distinct  from  Artemisia.  After  the  ehmination 
of  the  American  species,  recently  referred  to  it,  but  which  belong  to  Artemisia,  Cros- 
sostephium has  good  characters  as  a  natural  monotypic  genus. 


34  GENUS   ARTEMISIA. 

ORIGIN  AND  DEVELOPMENT  OF  THE  SECTIONS. 

The  first  attempt  at  a  systematic  arrangement  of  species  now  referred  to  Artemisia 
was  that  of  Tournefort  in  the  latter  part  of  the  eighteenth  century.  This  early  botanist 
pointed  out  certain  characters  of  some  importance,  such  as  the  pubescence  or  the  lack 
of  it  on  the  receptacle,  and  published  a  synopsis  of  the  forms  known  at  that  time  (Inst. 
Rei  Herb.,  457-460,  1700).  These  were  arranged  under  three  genera,  namely,  Absin- 
thium, Ahrotanum,  and  Artemisia.  Since  Tournefort's  system  was  based  largely  upon 
gross  external  characters,  and  especially  upon  aspect,  it  led  to  unnatural  groupings, 
which  were  abandoned  by  later  workers  in  the  Compositae,  although  his  generic  names 
have  been  retained  for  certain  of  the  sections.' 

Linnaeus,  in  the  Species  Plantarum,  united  Tournefort's  three  genera  under  the  one 
name  of  Artemisia,  thus  establishing  the  genus  as  now  generally  accepted.  He  made 
only  specific  use  of  the  receptacular  character  indicated  by  Tournefort  and  based  his 
divisions  of  the  genus,  which  were  not  indicated  by  section  names,  upon  the  unimportant 
characters  of  habit,  inflorescence,  and  foliage. 

A  notable  advance  was  made  when  Cassini  established  the  genus  Oligosporus  in  1817 
to  accomodate  those  Artemisias  in  which  the  flowers  in  each  head  are  of  two  sorts,  i.  e., 
marginal  pistillate  flowers  and  central  perfect  ones,  the  latter  with  abortive  or  at  least 
sterile  achenes.  This  group  corresponds  to  the  present  section  Dracunculus.  The  other 
species  were  all  assigned  to  the  genus  Artemisia,  Absinthium  not  being  recognized. 
Cassini's  treatment  was  adopted  by  Lessing  (Synopsis  Gen.  Comp.,  264,  1832),  who 
also  recognized  three  subgenera  of  Artemisia,  based  upon  features  which  had  in  the 
meantime  been  emphasized  by  Besser. 

While  all  of  the  above  workers  made  certain  contributions  toward  a  natural  arrange- 
ment of  the  species,  it  was  more  than  a  hundred  years  after  the  publication  of  Tourne- 
fort's studies  before  a  rational  and  comprehensive  natural  system  was  proposed.  This 
was  by  the  Russian  botanist  Besser,  who  published  his  results  in  various  papers,  including 
the  first  part  of  what  was  designed  to  be  an  extensive  and  fully  illustrated  monograph 
of  the  genus.  2 

The  monograph  projected  by  Besser  was  never  completed,  because  of  his  death  in 
1842,  but  a  masterly  summary  of  his  studies  is  presented  in  DeCandolle's  Prodromus 
(6:93-127,  1837).  The  subdivisions  of  the  genus  as  established  by  Besser,  together  with 
the  characters  assigned  are  as  follows : 

Section  I.  Dracuncidus.     Heads  heterogamous;  marginal  flowers  pistillate  (and  fertile);  central  flowers  perfect  but 

sterile;  receptacle  glabrous. 
Section  II.  Seriphidium.     Heads  hoinogamous  (flowers  all  perfect  and  fertile) ;  receptacle  glabrous. 
Section  III.  Abrotanum.     Heads  heterogamous;  marginal  flowers  pistillate  (and  fertile);  central  flowers  perfect  and 

fertile;  receptacle  glabrous. 
Section  IV.  Absinthium.     Heads  heterogamous;  marginal  flowers  pistillate  (and  fertile);  central  flowers  perfect  and 

fertile;  receptacle  hairy. 

Although  Besser  apparently  missed  the  evolutionary  significance  of  his  classification, 
it  has  the  decided  virtue  of  being  natural.  It  is  based  primarily  upon  fundamental 
differences  in  floral  structure,  and  therefore  always  will  be  used  as  the  basis  for  any 

'Gaertner,  Meyer,  and  Scherbiua  (Fl.  Wctterau  3  :  196,  1801)  retain  the  Tournefortian  genua  "Abaynthium"  with  one 

species,  namely  A.  rulgarius  Bauhin,  that  is,  A.  absinthium  Linnaeus. 
•Besser,  W.S.     1829.     Synopsis  Absinthiorum.     Bull.  See.  Imp.  Mosc.  1  :  219-265. 

.     1831.     de  Seriphidiis  seu  de  sectione  Ilia  Artemisiarum  Linnaei.     Bull.  Soc.  Imp.  Mosc.  7  :  1-46. 

.     1834.     Tentamen  pe  Abrotanis  seu  de  sectione  Ilda  Artemisiarum  Linneai.     Nouv.  Mem.  Soc.  Mosc.  3;  1-92. 

.     1835.     Dracunculi  seu  de  sectione  IVta  et  ultima  Artemisiarum  Linnaei.     Bull.  Soc.  Imp.  Mosc.  8  :  1-95. 

.     1836.     Supplementum  ad  synopsin  Absynthiorum  tentamen  de  Abrotanis,  dissertationem  de  Seriphidiis  atque 

de  Dracunculis.     lb.  9  :  1-115. 

.     1841.     Revisio  Artemisiarum  Musei  Regii  Berolinensis,  cuius  partem  constituit  Herb.  Wildenovianum  icatituta. 

Linnaea  15  :  83-111. 
.     1846.     Monographae  Artemisiarum,  Section  I.     Dracunculi  fruUscentet.     Mem.  Sav.  Etr.  St.  Peterab.  6  :  1-44. 


ORIGIN   AND    DEVELOPMENT   OF   THE    SECTIONS.  35 

scheme  that  aims  at  a  representation  of  relationships.  It  will  be  readily  seen,  however, 
that  the  four  sections  are  not  of  equal  rank,  the  third  and  fourth  differing  from  each 
other  only  by  the  absence  or  presence  of  hairs  on  the  receptacle.  This  was  noticed  by 
Gray,  for  in  his  Synoptical  Flora  we  find  Abrotanum  and  Absinthium  united  into  what 
is  called  Euartemisia,  the  other  two  sections  of  Besser  being  retained  with  the  same 
Umits  as  in  the  Prodromus.  The  logic  of  this  reduction  is  sound,  but  for  practical  pur- 
poses it  seems  better  to  retain  Absinthium  and  Abrotanum  as  sections. 

Up  to  the  present  time  students  of  Artemisia  seem  to  have  contented  themselves 
with  its  subdivision  into  more  or  less  natural  sections,  but  have  not  been  much  concerned 
with  the  phyletic  arrangement  of  these  sections.  In  even  the  latest  treatments  the 
section  Dracunculus  is  still  found  at  the  beginning,  although  there  is  abundant  evidence 
that  this  is  a  more  highly  specialized  type  than  Abrotanum,  and  that,  with  the  possible 
exception  of  Seriphidium,  it  is  the  most  highly  developed  of  all  of  the  groups.  A 
considerable  rearrangement  is  therefore  necessary  in  order  to  bring  the  sequence  into 
harmony  with  well-established  principles  of  phylogeny.  The  various  groups,  their 
distinguishing  characteristics,  and  their  probable  relationships  are  indicated  in  the 
accompanying  chart  (fig.  1)  and  may  be  expressed  in  key  form  as  follows: 

Heads  heterogamous,  the  marginal  flowers  pistillate. 

Central  flowers  fertile,  with  normally  developed  achenes. 

Receptacle  not  hairy 1.  Abrotanum. 

Receptacle  long-hairy ' 2.  Absinthium. 

Central  flowers  sterile,  their  achenes  aborted 3.  Dracunculus. 

Heads  homogamous,  the  marginal  flowers  wanting 4.  Seriphidium. 


Fio.  1. —  Phylogenetic  chart  of  the  sectiona  of  Artemina. 

This  arrangement  is  based  on  the  assumption  that  Artemisia  is  derived  from  an  ancestor 
resembUng  Chrysanthemum  or  Tanacetum,  in  which  the  ray-flowers  are  present  and 
pistillate  and  the  disk-flowers  perfect  and  fertile.  In  the  genus  Tanacetum  section 
Sphaeromeria  there  is  an  evident  reduction  in  the  ligule  of  the  ray-flowers,  proceeding 
in  some  cases  to  its  complete  elimination,  when  the  corolla  closely  approximates  that  of 
Abrotanum  in  structure  and  shape. 


36  GENUS   ARTEMISIA. 

The  most  primitive  of  the  sections  is  Abrotanum.  This  seems  certain  from  the  con- 
sideration that  all  others  exhibit  very  marked  peculiarities  which  could  come  about 
only  through  the  modification  of  an  Abrotanum-like  ancestor.  Thus,  forms  without 
ray-flowers  or  with  aborted  disk-flowers  certainly  were  derived  from  a  form  in  which 
both  ray-flowers  and  disk-flowers  were  present  and  fertile.  The  evident  connection  of 
certain  species  of  Ahrotanum  with  the  still  more  primitive  Crossostephium  is  additional 
evidence  pointing  in  the  same  direction.  Abrotanum  is  by  far  the  largest  of  the  sections 
and  is  widely  distributed  in  both  the  New  and  the  Old  World.  The  species  are  mostly 
perennial  herbs,  the  best  known  of  which  is  the  common  mugwort,  or  sagewort  (A. 
vulgaris.) 

Absinthium  is  an  assemblage  of  European  and  northern  herbaceous  perennials.  It 
differs  from  Abrotanum  solely  in  the  presence  of  a  copious  villous  pubescence  on  the 
receptacle.  Since  this  character  does  not  reappear  elsewhere  in  the  genus,'  the  group  is 
considered  as  a  derivative  or  subdivision  of  Abrotanum  which  has  not  led  to  any  decided 
development.  Its  distinguishing  character  is  not  such  as  to  warrant  its  recognition  as  a 
separate  section,  yet  it  is  continued  because  of  usage  and  practicability. 

The  two  remaining  sections  of  Artemisia  have  been  evolved  by  the  same  process  of 
reduction  as  that  exhibited  in  the  development  of  the  genus  itself.  The  loss  of  the 
pappus  and  of  fully  functional  ray-flowers  has  been  followed  by  the  progressive  reduction 
of  the  flowers  of  the  head.  This  appears  to  arise  in  consequence  of  the  fact  that  the 
ray-flowers  and  disk-flowers  had  come  to  have  essentially  the  same  function,  and  hence 
to  compete  with  one  another  for  the  food-supply  brought  to  each  head.  A  demand  for 
food  in  excess  of  the  supply  would  inevitably  bring  about  the  reduction  and  loss  of  the 
less  important  parts.  This  might  operate  in  either  of  two  directions,  namely,  to  eliminate 
the  unnecessary  pistils  in  the  disk-flowers  or  to  effect  the  loss  of  the  ray-flowers,  already 
much  reduced  in  functional  value.  Both  of  these  specializations  resulted  in  economy 
of  material  and  increase  of  parental  care,  and  have  actually  been  carried  out  in  the 
respective  sections,  DracuncuJus  and  Seriphidium. 

The  section  Dracunculus,  which  comprises  herbs  and  low  shrubs  of  both  hemispheres, 
is  here  taken  as  a  development  from  Abrotanuin.  It  is  considered  as  a  farther  advance, 
for  not  only  are  the  calyx-limb  and  stamens  of  the  marginal  flowers  wanting  as  in  that 
section,  but  the  pistil  of  the  central  flowers  ceases  to  function,  so  that  the  central  achenes 
are  uniformly  sterile  and  in  most  cases  entirely  aborted.  There  is  thus  a  complete 
division  of  labor  between  the  two  sorts  of  flowers,  the  marginal  ones  functioning  exclu- 
sively as  pistillate,  the  others  as  staminate. 

Seriphidium  is  a  comparatively  small  group  in  this  country,  where  the  representatives 
are  all  shrubs  or  at  least  woody  perennials,  commonly  known  as  sagebrush  {A.  tridentata, 
etc.).  In  the  Old  World  there  are  many  herbaceous  as  well  as  shrubby  species,  but  it 
is  not  certain  that  these  are  of  the  same  phylogenetic  stock  as  the  American  ones.  It 
is  possible  that  the  characters  of  the  section  have  been  developed  independently  on  the 
two  continents.  If  this  is  the  case,  then  Seriphidium  as  now  accepted  is  not  a  natural 
subdivision.  Whether  of  one  origin  or  of  two,  this  section,  like  Dracunculus,  is  probably 
a  derivative  of  Abrotanum,  but  its  evolution  has  proceeded  along  quite  different  lines. 
Instead  of  the  central  flowers  becoming  essentially  staminate,  they  have  remained 
perfect  and  the  achenes  are  fertile,  but  the  marginal  flowers  have  entirely  disappeared, 
thus  rendering  the  head  homogamous  through  reduction.  This  may  be  viewed  as  the 
result  of  competition  between  the  central  and  the  marginal  flowers  of  the  head,  the  former 
having  succeeded  in  drawing  food  away  from  the  latter,  which  in  consequence  have 
failed  to  function  and  have  finally  disappeared  from  the  heads.     This  is  an  advantage 

'  The  receptacle  in  A.  calijornica  \a  sometimes  puberulent,  but  never  long-hairy. 


CRITERIA.  37 

SO  far  as  the  species  as  a  whole  are  concerned,  as  is  indicated  by  the  fact  that  although 
the  average  number  of  flowers  in  the  head  is  much  less  in  Seriphidium  than  in  any  other 
section,  the  species  are  abundant  in  individuals  and  widely  distributed.  An  intermediate 
stage  between  Abrotanum  and  Seriphidium  is  indicated  by  A.  bigelovi,  a  low  shrub  with 
the  aspect  of  certain  forms  of  A.  tridentata.  Here  the  ray-flowers,  recognized  by  their 
peculiar  2-toothed  corollas,  are  usually  present,  although  reduced  in  number  to  only 
one  or  two,  but  occasionally  entirely  suppressed,  the  head  then  consisting  of  only  two 
or  three  flowers  with  regular  5-toothed  corollas.  Perhaps  this  species  represents  the 
beginning  of  the  Seriphidium  line,  where  the  evolution  of  homogamous  from  hetero- 
gamous  heads  is  still  in  progress. 

■  In  accordance  with  this  discussion  of  the  relationships  of  the  various  sections  of 
Artemisia  to  one  another,  the  sequence  in  the  following  treatment  conforms  to  the 
diagram  and  key  here  presented,  and  hence  departs  quite  radically  from  that  found  in 
any  preceding  monograph.  While  this  may  at  first  seem  somewhat  confusing,  it  is 
believed  that  the  phylogenetic  basis  on  which  it  rests  is  ample  justification  for  its 
adoption. 

CRITERIA  FOR  THE  RECOGNITION  OF  SPECIES  AND  SURSPECIES. 

It  is  obvious  that  the  best  criteria  are  those  which  have  to  do  with  the  structure  and 
development  of  the  flowers  and  particularly  those  of  the  fruits.  Such  differences  in 
character  are  not  wanting  in  Artemisia,  but  they  are  extremely  few.  It  is  not  surprising, 
therefore,  to  find  that  these  are  of  such  importance  that  they  are  used  as  a  basis  for  the 
sections  of  the  genus.  Thus,  the  suppression  of  the  ray-flowers  in  some  cases  and  the 
complete  disappearance  of  the  disk-achenes  in  others  are  both  recognized  as  sectional 
characters,  as  already  discussed  in  the  preceding  chapter.  Other  characters,  such  as 
minor  modifications  in  floral  structure,  and  especially  that  of  the  involucre  and  the  more 
vegetative  parts  of  the  plant,  will  now  be  taken  up  in  detail. 


-Achenes  of  Artemisia:  a,  6,  from  a  single  plant  of  ^4.  iridcntato  typica  (73923  UC);  c,  d,  from  another  plant  of  A. 
tridentata  typica  (71705  UC);  e,  /,  from  a  single  plant  of  A.  carta  (Hall  11673);  g,  h,  from  another  plant  of  A. 
cana  (Hall  11690).     All  of  the  achenes  are  more  or  less  granular-glanduliferous.     All  X   16. 


Achene. — The  shape  of  the  achene  in  Artemisia  apparently  is  a  modification  of  the 
prism.  In  some  species  it  is  still  essentially  prismatic,  with  four  faces,  but  there  always 
is  a  more  or  less  evident  narrowing  toward  the  base  and  the  summit  is  truly  truncate 
in  only  a  few  cases.  The  nearest  approach  to  the  prism  is  seen  in  the  achenes  of  some  of 
the  subspecies  of  A.  norvegica,  A.  tridentata,  and  A.  cana,  as  shown  on  the  respective 
plates.  The  variation  within  a  species,  and  even  on  a  single  plant,  is  greater  than  would 
be  expected.  This  variation  is  seen  especially  in  the  extent  of  incurving  at  the  summit 
and  in  the  prominence  of  the  angles,  these  latter  often  being  reduced  to  ribs  or  nerves, 
or  in  some  cases  they  are  quite  obsolete.  Something  of  this  is  shown  in  the  accompany- 
ing figures,  where  it  will  be  seen  that  very  unlike  achenes  occur  in  some  of  the  species. 


38  GENUS   ARTEMISIA. 

Differences  in  shape  and  especially  in  size  are  often  due  merely  to  differences  in 
maturity.  This  is  so  evident,  and  fully  ripe  achenes  are  so  seldom  represented  in  herbaria 
that  a  statement  of  size  in  a  diagnosis  is  rarely  of  value.  On  the  contrary,  it  is  often 
positively  misleading.  For  these  reasons  the  size  is  not  indicated  in  the  descriptions 
in  the  present  paper. 

Notwithstanding  the  considerable  fluctuation  within  even  a  single  species,  achenial 
characters  serve  somewhat  as  a  guide  in  the  matter  of  natural  groupings.  Thus,  for 
example,  in  the  section  Abrotanum  the  achenes  are  comparatively  short  and  tend 
toward  the  formation  of  a  border  or  crown  at  the  broad  summit.  This  border  fits 
loosely  around  the  base  of  the  corolla-tube.  It  is  most  noticeable  in  A.  pontica,  A. 
abrotanum,  and  A.  calif ornica,  all  of  which  seem  to  be  primitive  in  most  of  their  other 
characters.  The  crown-like  summit  is  here  perhaps  a  remnant  of  the  disk  which  bore 
the  pappus  in  those  forms  precedent  to  Artemisia  in  the  line  of  evolutionary  develop- 
ment. A  similar  but  less  definite  crown  persists  also  in  section  Seriphidium,  but  here 
it  is  usually  associated  with  more  elongated  achenes,  often  with  four  or  five  raised 
longitudinal  ribs  or  angles. 

Style-branches. — The  usual  condition  of  the  style  is  2-cleft  at  maturity,  as  in  most 
Compositae.  In  the  ray-flowers  the  branches  are  either  acute  or  thickened  and  somewhat 
obtuse,  while  in  the  disk-flowers  the  branches  are  almost  uniformly  truncate  at  apex 
and  more  or  less  distinctly  fimbriate  or  at  least  penicillate.  In  some  cases,  however, 
the  style  in  the  disk-flowers  is  undivided  and  capped  by  a  disk  with  a  roughened  or 
fimbriate  border.  This  is  certainly  a  development  from  the  2-cleft  style,  brought  about 
by  the  fusion  of  the  branches.  It  obtains  only  in  certain  species  of  the  section  Dracun- 
culus.  This  character  of  the  peltate  stigmas  has  sometimes  been  used  for  the  purpose 
of  distinguishing  the  dracunculus-campestris  group,  in  which  the  style  is  said  to  be  undi- 
vided, from  the  filifolia-pedatifida  group,  in  which  the  style  is  described  as  usually  more 
or  less  2-cleft.  An  examination  of  seven  collections  of  A.  dracunculus  from  widely  sepa- 
rated locaUties  discloses  the  fact  that  in  all  of  these  the  style  is  cleft  into  two  lobes, 
which  are  erect,  or  nearly  so,  as  in  A.  filifolia.  Frequently  the  branches  stand  so  close 
together  that  they  appear  to  be  united,  yet  when  lightly  pressed  with  a  needle  they 
spring  apart  or  even  recurve.  No  instance  of  complete  fusion  was  encountered  in  this 
species,  although  the  condition  doubtless  exists.  Fusion  is  apparently  more  common 
in  A.  campestris,  5  subspecies  of  which  were  studied,  with  42  as  the  total  number  of 
flowers  examined.  In  30  of  these  the  style-branches  were  completely  fused,  while  in 
the  remaining  12  they  were  separate  at  least  along  one  margin.  Completely  fused 
branches  and  fully  cleft  styles  are  frequently  found  in  the  same  head:  In  some  cases 
the  fusion  is  evident  only  along  one  side,  the  result  being  a  cylinder  split  down  for  a 
short  distance  along  a  single  line. 

Passing  to  A.  filifolia,  it  was  found  that  both  conditions  always  obtained  on  the  same 
plant  as  far  as  examined,  a  small  majority  of  the  styles  having  fused  branches.  A 
similar  condition  prevails  in  A.  pedatifida,  and  in  this  species  the  various  degrees  of 
fusion  are  especially  well  represented  (e.  g.,  Nelson's  7058,  from  Sweetwater  County, 
Wyoming.)  Two  of  the  stages  are  shown  on  plate  16.  In  A.  spinescens  the  branches 
are  always  completely  united,  as  far  as  has  been  observed. 

The  fused  character  of  the  styles  is  thus  seen  to  be  a  variable  trait,  occurring  irregu- 
larly in  one  section  of  the  genus  and  hence  of  little  specific  and  of  no  sectional  or  sub- 
generic  value. 

Corolla. — The  size  of  the  disk-corollas  is  sometimes  of  very  definite  value  as  a  specific 
and  subspecific  character.  Certain  species,  notably  A.  parryi,  A.  stelleriana,  A.  pattersoni, 
and  A.  pedatifida,  stand  off  very  sharply  in  this  feature  from  their  nearest  allies.    The 


CRITERIA.  39 

shape  differs  slightly  between  the  species,  but  this  can  not  be  expressed  with  sufficient 
definiteness  to  render  the  character  of  much  descriptive  value.  The  central  flowers 
are  always  regularly  5-lobed.  The  marginal  corollas,  on  the  other  hand,  are  so  highly 
modified  and  there  is  so  much  variation  even  in  plants  which  are  otherwise  almost 
identical,  that  their  use  is  of  but  shght  importance  in  taxonomic  work. 

The  color  of  the  flowers  is  sometimes  used  as  the  sole  criterion  for  the  recognition  of 
so-called  species,  quite  contrary  to  usage  in  connection  with  other  flowering  plants. 
At  the  best,  color  can  be  looked  upon  only  as  indicating  strains  or  races  when  forms  are 
found  to  differ  by  this  feature  alone.  In  some  cases  color  is  associated  with  the  amount 
and  quality  of  the  light.  Thus,  A.  calif ornica  normally  has  yellowish  or  brownish  flowers, 
but  along  the  desert  borders  they  are  commonly  red.  Similarly,  the  flowers  of  A. 
norvegica  are  pale  yellow  in  the  Rocky  Mountains,  but  Arctic  forms  are  frequently 
pink  or  red.  Rydberg  has  made  use  of  color  in  retaining  A .  purshiana  as  distinct  from 
A.  gnaphalodes  (N.  Am.  Fl.  34:273,  1916)  and  numerous  observations  confirm  his  state- 
ment that  the  latter  form,  with  dark-brown  or  purplish  corollas,  occurs  only  to  the  east 
of  the  Rocky  Mountains.  West  of  this  area  only  the  yellow-flowered  "purshiana"  is 
found,  but  unfortunately  for  the  correlation  with  geographic  distribution,  this  occurs 
also  at  times  within  the  area  assigned  to  the  purple-flowered  form  (see  further  on,  p.  86). 

The  futility  of  attempting  to  use  flower-color  as  a  specific  or  even  a  subspecific  criterion 
in  the  field  is  evidenced  by  studies  made  on  Coal  Creek,  in  the  Teton  Mountains  of 
Wyoming  (samples  preserved  at  herbarium.  University  of  California,  11444,  11445). 
Here,  at  2,500  meters  altitude,  there  grows  an  abundance  of  A.  vulgaris  flodmani,  the 
plants  forming  colonies  of  considerable  extent.  In  one  of  these  the  corollas  were  all  pure 
greenish-yellow  or  at  the  most  edged  with  pale  purple,  but  neighboring  colonies  were  all 
deep  purple.  While  this  difference  was  not  great,  it  was  positive  and  each  plant  could 
be  placed,  on  close  examination,  in  either  the  yellow  or  the  purple  group.  Therefore,  if 
this  character  is  to  be  used  for  the  separation  of  species  in  one  part  of  the  genus,  it  should 
be  appUed  throughout,  and  this  would  result  in  breaking  up  flodmani,  already  too  close 
to  discolor,  into  two  subspecies  and  assigning  these  to  identical  habitats.  A  similar 
division  would  presumably  be  necessary  for  many  other  species  and  subspecies.  Such 
procedure,  while  possibly  desirable  after  a  close  genetic  analysis  and  after  a  method 
has  been  devised  for  classifying  these  minor  forms,  is  neither  necessary  nor  advisable 
at  the  present  time.    The  pubescence  of  the  corolla  will  be  referred  to  later  (p.  43). 

Number  and  reduction  of  flowers  in  the  head. — The  reduction  or  complete  suppression 
of  certain  types  of  flowers  in  the  head  was  used  by  Besser  as  the  chief  basis  for  his  classi- 
fication into  sections,  and  it  is  still  the  most  important  character  available  for  this  pur- 
pose. All  species  of  Artemisia  may  be  classed  as  either  heterogamous  or  homogamous. 
In  the  former  the  head  consists  of  an  outer  circle  of  ray-flowers  and  an  inner  one  of  disk- 
flowers,  these  two  kinds  of  flowers  being  rather  easily  distinguished  by  reference  to  the 
plates.  Homogamy  has  been  brought  about  through  a  complete  elimination  of  ray- 
flowers.  This  is  regularly  the  case  in  the  section  Seriphidium.  That  the  reverse  has  not 
been  the  direction  of  evolution— that  is,  that  heterogamy  has  not  arisen  from  homog- 
amy— is  evidenced  by  a  consideration  of  the  fact  that  such  an  assumption  would 
necessitate  the  corollary  of  the  development  of  ray-flowers  in  Artemisia.  This  in  turn 
would  lead  either  to  the  assumption  that  the  Artemisias  were  the  progenitors  of  all 
of  the  radiate  Compositae  or  to  the  polygenetic  origin  of  this  character.  If  further 
evidence  is  needed  it  is  seen  in  the  nature  of  the  ray-corolla  when  this  is  present.  It  is 
always  an  apparently  functionless  structure  with  an  irregular  orifice  and  is  plainly  a 
vestige  of  the  regular  corolla  and  not  so  modified  as  to  give  evidence  of  being  an  incipient 
ligulate  corolla.    A  connection  between  heterogamy  and  homogamy  is  apparently  found 


40  GENUS   ARTEMISIA. 

in  A .  bigelovi,  a  species  which  has  ray-flowers,  but  these  are  very  few  in  number  and  even 
entirely  wanting  in  some  heads,  while  in  all  of  its  other  characters  it  is  similar  to  the 
uniformly  homogamous  A.  tridentata. 

The  number  of  ray-flowers  and  of  disk-flowers  in  a  head  is  often  of  specific  value. 
These  numbers  are  therefore  always  stated  in  descriptions  and  are  used  to  some  extent 
in  keys.    The  extent  of  variation  is  again  indicated  in  the  tables. 

The  abortion  of  pistils  of  the  disk-flowers  was  also  used  by  Besser  as  a  basis  for  sec- 
tional classification.  This  abortion  consists  in  the  almost  complete  reduction  of  the 
ovary  and  consequently  of  the  achene,  and  in  a  considerable  modification  of  the  style. 
The  stigma  in  these  aborted  pistils  is  of  course  functionless.  All  of  the  species  showing 
this  remarkable  modification  were  placed  by  Besser  in  his  section  Dracunculus,  and  there 
is  no  apparent  reason  for  assuming  that  the  section  is  other  than  a  natural  one.  The 
character  is  obviously  to  be  looked  upon  as  one  indicating  a  high  order  of  development, 
and  Dracunculus  is  therefore  accepted  as  one  of  the  two  most  highly  specialized  sections 
of  the  genus. 

Involucre. — The  structure  of  the  involucre  and  the  bracts  often  furnishes  important 
specific  criteria  in  the  Compositae.  In  Artemisia,  however,  the  involucre,  while  yielding 
some  characters  of  value,  is  on  the  whole  quite  disappointing.  The  size  of  the  involucre 
is  used  to  a  very  considerable  extent,  but  it  should  be  understood  that  this  is  usually 
associated  with  the  number  of  flowers  in  the  head.  In  stating  the  size  it  is  found  that 
the  height  is  much  more  useful  than  the  breadth.  This  is  simply  because  the  height  is 
a  dimension  which  can  be  measured  with  definiteness,  whereas  the  breadth  depends 
not  only  upon  the  state  of  maturity,  but,  in  the  case  of  herbarium  specimens,  upon  the 
pressure  which  has  been  applied  in  their  preparation.  The  largest  heads  in  the  species 
found  in  America  occur  in  A.  stelleriana.  The  heads  are  here  so  large  that  the  species 
may  always  be  distinguished  by  this  character  alone,  except  for  an  occasional  very  large 
head  of  A.  vulgaris  tilesi.  In  A.  vulgaris  there  is  a  very  considerable  range  of  size,  as 
indicated  by  the  tables,  but  it  is  noteworthy  that  one  subspecies,  namely,  litoralis,  has 
an  involucre  regularly  so  narrow  that  its  dimensions  never  overlap  those  of  any  other. 
The  fluctuations  both  in  height  and  breadth  within  subspecies  and  within  species  is 
indicated  in  a  number  of  the  tables. 

The  relative  length  of  bracts  within  a  single  involucre  has  been  used  in  many  instances 
by  Rydberg  in  his  treatment  of  the  genus  in  the  North  American  Flora.  It  is  true  that 
the  outer  bracts  are  sometimes  so  differently  set  off  from  the  inner  that  this  character 
of  relative  length  becomes  of  importance,  but  it  is  impossible  to  detect  the  sharp  difi'er- 
ences  that  one  is  led  to  assume  from  his  descriptions.  The  absence  of  differences  where 
they  are  supposed  to  exist  is  indicatedin  thefigures  on  pages  124  and  149.  The  outer  bracts 
are  usually  shorter  than  the  inner  and  sometimes  they  have  their  own  peculiar  shape,  but 
the  gradation  is  so  shght  and  the  external  bracts  undergo  so  many  modifications  that 
such  criteria  must  be  used  with  exceeding  caution.  Even  the  inner  bracts  are  not  con- 
stant in  the  shape  of  the  exposed  portions.  The  number  is  sometimes  helpful,  and  this 
is  brought  out  together  with  the  extent  of  the  variation  in  the  tables,  where  actual 
counts  of  large  series  are  indicated. 

Inflorescence. — By  far  the  most  common  type  of  inflorescence  is  the  panicle.  All 
others  are  modifications  of  this.  When  the  panicle  is  narrow  and  much  simplified,  it 
may  be  either  racemose  or  spicate.  When  it  is  much  shortened  and  condensed  the 
panicle  becomes  capitate.  These  various  forms  of  inflorescence  are  modifications  of 
the  paniculate  type,  as  seen  from  the  frequent  series  of  intergradations  that  can  be 
found  almost  anywhere.  They  are  also  derived  forms  as  evidenced  by  the  fact  that 
the  panicle  is  by  far  the  most  abundant  and  that  it  occurs  in  forms  which  are  primi- 
tive in  their  other  features.    In  only  one  case  does  the  modified  type  of  inflorescence  run 


CRITERIA.  41 

parallel  with  specific  characters.  This  is  in  A.  senjavinensis,  in  which  the  heads  are 
always  in  a  dense  terminal  cluster,  as  far  as  known.  It  should  be  noted,  however,  that 
this  type  of  inflorescence  also  occurs  in  certain  subspecies  of  the  very  closely  related 
A.  norvegica. 

Leaves.— The  leaves  in  Artemisia  are  always  alternate  and  simple,  but  in  almost  all 
other  respects  they  run  through  long  series  of  variations.  They  are  evidently  plastic 
structures.  They  range  from  entire  to  twice-pinnatifid,  even  in  a  single  species.  Terete 
leaves  occur  among  the  American  species  only  when  this  condition  has  been  brought 
about  by  the  folding  of  the  margins,  as  in  abrotanum,  filifolia,  etc.  It  seems  that  these 
tightly  revolute  leaves  can  be  changed  back  to  plane  leaves  by  a  change  in  the  environ- 
ment. For  example,  in  A.  calif  arnica  the  leaves  and  their  lobes  are  usually  revolute  and 
terete,  yet  in  vigorous  young  growth  the  lobes  flatten  out  and  become  1.5  to  2  mm. 
broad.  This  is  seen  even  in  the  northerly  part  of  the  range  of  the  species,  while  to  the 
south,  and  especially  on  some  of  the  islands  off  the  coast  of  southern  California,  it  is 
very  pronounced.  Somewhat  different  seems  to  be  the  case  of  a  very  narrow-leaved 
form  of  Artemisia  cana.  This  species  usually  has  leaves  2  to  4  mm.  wide.  It  sometimes 
happens  that  the  plants  growing  with  the  normal  form  have  leaves  only  1  mm.  wide, 
and  no  intermediate  forms  appear.  The  exact  reason  for  this  is  not  known,  but  possibly 
the  narrow-leaved  type  is  a  mutation  from  the  broader-leaved  one.  The  venation  of  the 
leaf  is  sometimes  very  prominent  and  is  then  an  aid  in  the  recognition  of  the  species. 
This  is  particularly  true  in  the  case  of  A.  rigida. 


FlQ.  3. — Leaves  of  Artemisia  vulgaris  hcterophylla,  to  show  variation  in  outline:  a,  leaf  from  plant  growing  on  a  moist 
northerly  slope  (most  leaves  on  this  plant  were  of  this  type,  with  long,  spreading  lobes) ;  b,  leaf  from  plant  of  loose 
soil  fairly  moist  (the  moderately  spreading  lobes  are  characteristic  of  the  plant) ;  c,  d,  e,  /,  g,  common  types  of 
leaves  on  southerly  exposure.     AJl  from  the  Oakland  Hills,  California.     All  X  0.4.     See  also  fig.  7,  p.  74. 


The  extent  and  nature  of  the  lobing  of  leaves  furnish  useful  criteria  in  a  few  cases. 
Thus,  in  certain  species  the  blade  is  uniformly  divided  into  fiUform  lobes,  in  others  a 
unique  type  of  dentation,  confined  to  the  summit  of  the  leaf,  furnishes  a  useful  clue  as 
to  relationships.  In  most  species,  however,  the  variation  is  so  extensive  that  leaf- 
characters  fail  almost  entirely,  even  for  the  recognition  of  subspecies  and  varieties. 
All  students  of  the  genus  have  attempted  to  use  them,  but  those  most  familiar  with  the 
plants  in  the  field  are  the  least  inclined  to  attach  importance  to  cut  of  leaf.  Thus, 
Piper,  in  speaking  of  species  here  referred  to  A.  vulgaris,  expresses  the  opinion  that  leaf 
contour  is  worthless  as  a  character  and  that  its  use  leads  to  an  artificial  disposition  of 
species  and  subspecies  (Contr.  U.  S.  Nat.  Herb.  11:588-589,  1906).  Evidence  of  a 
similar  nature  is  recorded  very  incompletely  in  figure  3,  where  seven  different  cuts  of 


42  GENUS   ARTEMISIA. 

leaf  are  shown,  all  from  plants  growing  in  a  small  range  of  hills  in  California.  Many  inter- 
mediate forms  could  also  be  shown.  While  field  studies  are  necessary  fully  to  comprehend 
the  extent  of  this  variation,  some  attempts  have  been  made  to  bring  the  evidence  into 
herbaria.  Thus,  for  example,  at  the  United  States  National  Herbarium  is  a  series  of  13 
sheets  of  a  form  of  A.  vulgaris,  filed  under  A.  atomifera  Piper,  showing  gradations  in 
leaf  from  entire  or  merely  3-toothed  to  divided  with  3  spreading  lobes  on  each  side, 
these  lobes  separate  nearly  to  the  midrib  (Piper  6466).  A  still  more  extensive  series 
has  been  collected  near  Spokane,  Washington,  by  Miss  Evelyn  Moore.  These  are  now 
on  file  at  the  University  of  California  under  A.  vulgaris  candicans. 

An  attempt  has  been  made  to  correlate  these  leaf-forms  with  ecologic  conditions,  and 
some  success  has  resulted  at  least  as  regards  leaf-area.  Thus,  wide  leaves  are  most 
frequent  in  the  north  and  along  the  Pacific  Coast,  whereas  narrower  leaves  and  lobes 
become  more  abundant  as  a  species  extends  its  range  to  the  south  and  especially  to  the 
arid  and  more  strongly  illuminated  portions  of  the  southwest.  The  leaves  shown  in 
figure  12  (p.  95)  suggest  an  edaphic  effect  of  environment,  since  all  were  from  the  same 
climatic  area.  It  will  be  noted  from  the  explanation  that  the  broader  and  more  deeply 
cut  leaves  are  from  the  better  and  moister  soil,  while  the  narrower,  entire  ones  are  from 
stony  arid  slopes.  Nature  and  extent  of  lobing  can  not  always  be  correlated  with  environ- 
mental conditions,  as  shown  by  the  frequent  occurrence  of  very  unlike  foliage  on  plants 
growing  under  apparently  identical  conditions.  Leaves  hke  those  labeled  c  to  /  of  figure  3 
are  found  on  plants  growing  side  by  side.  Much  experimental  work  will  be  necessary 
before  the  significance  of  such  variations  will  be  understood. 

The  illustrations  thus  far  referred  to  are  mostly  of  the  polymorphous  A.  vulgaris, 
but  similar  conditions  are  found  in  other  species.  Variations  are  illustrated  to  a  limited 
extent  in  the  plates,  particularly  in  those  of  A.  tridentata,  and  additional  examples  are 
shown  in  figures  21  and  22  (pp.  144,  145). 

Stipule-like  appendages  have  been  noted  in  a  few  of  the  species  and  are  illustrated  in 
figure  10.  These  are  in  reality  lobes  which  have  become  isolated  from  the  body  of  the 
leaf  and  taken  up  positions  near  the  base  of  the  petiole,  as  is  evident  from  their  lack  of 
constancy  in  number,  position,  and  size.  Sometimes  they  grade  insensibly  into  the 
more  conspicuous  lobes  of  the  blade.  They  supply  a  valuable  character  for  the  recog- 
nition of  A.  procera,  especially.  As  to  A.  vulgaris,  they  are  almost  uniformly  present 
in  subspecies  typica,  very  common  but  sometimes  wanting  in  arctica,  only  occasionally 
present  in  candicans  and  heterophylla,  and  almost  entirely  absent  from  the  other  American 
subspecies.  These  facts  are  of  much  value  as  corroborative  evidence  in  working  out  the 
phylogeny  of  these  forms. 

Stem  and  bark. — Among  the  herbaceous  species  it  is  found  that  certain  minor  characters 
have  been  used  to  some  extent  as  criteria.  The  reddening  of  the  stems  with  age  is  very 
noticeable  in  some  cases  and  is  at  least  a  tendency  which  is  helpful  in  the  detection  of 
certain  subspecies.  The  amount  of  pigment  formed  is  known  in  other  genera  to  be  so 
often  dependent  upon  the  amount  of  light  that  it  is  doubtful  if  the  color  is  of  more  than 
suggestive  importance  in  Artemisia.  The  striation  of  the  stem  is  quite  marked  in  some 
species,  while  others  have  smooth  stems.  This  is  again  of  minor  significance,  especially 
as  the  striation  is  often  masked  by  the  pubescence.  The  character  seems  to  be  of  some 
value  in  distinguishing  A.  tridentata,  in  which  the  striae  are  present,  but  which  often 
requires  the  removal  of  the  tomentum  for  their  detection,  from  the  very  similar  but 
botanically  distinct  A.  higelovi,  in  which  the  striations  are  entirely  wanting.  The 
bark  is  different  in  different  species,  but  it  requires  considerable  field  experience  to  make 
use  of  this  character.  In  cana,  rigida,  and  pygmoea  the  bark  is  dark  and  fibrous.  In 
tridentata  it  is  more  shreddy  and  peels  off  in  narrow  strips,  while  in  bigelovi  it  is  sheathing 
on  the  older  parts  of  the  stem  and  peels  off  in  sheets  rather  than  strips. 


CRITERIA.  43 

Roots. — The  true  roots,  as  contrasted  with  the  rootstocks  and  caudex  mentioned 
above,  have  not  been  used  for  purposes  of  classification.  The  root  system  of  A.  filifolia 
has  been  described  and  mapped  by  Weaver  (Carnegie  Inst.  Wash.  Pub.  286:73,  fig.  25, 
1919). 

Pubescence. — As  in  other  botanical  groups,  this  character  is  a  misleading  one  to  use, 
if  only  its  relative  abundance  and  the  accompanying  effect  on  the  general  appearance  of 
the  plant  are  taken  into  account.  Thus,  all  gradations  in  the  amount  of  pubescence  on 
different  parts  of  the  plant,  and  consequently  in  the  appearance  of  the  plant  itself,  are 
well  known  in  the  numerous  variads  of  A.  vulgaris.  More  important  is  the  persistence 
of  the  pubescence  when  this  is  present.  For  example,  the  behavior  of  tomentum  in 
the  subspecies  of  vulgaris  is  exceedingly  variable,  and  yet  certain  ones  exhibit  a  strong 
tendency  to  retain  the  tomentum,  while  others  have  an  equally  strong  tendency  to  drop 
it  as  the  parts  mature.  Even  more  important  is  the  nature  of  pubescence  itself.  This 
difference  in  the  character  of  the  trichomes  and  the  direction  they  take  in  regard  to  the 
surface  of  the  epidermis  is  especially  helpful  in  separating  norvegica  and  its  associates 
from  the  vulgaris  group  of  species.  In  the  former  the  pubescence,  when  present,  is 
spreading,  or  villous,  while  in  the  latter  it  is  more  or  less  appressed,  tangled,  and  therefore 
tomentose.  Yet  even  here  it  is  possible  to  select  forms  of  the  two  different  groups  that 
are  so  much  alike  in  this  character  that  their  separation  becomes  exceedingly  perplexing. 

The  pubescence  of  the  receptacle  is  a  matter  of  great  importance.  It  occurs  only  in 
one  section  of  the  genus,  namely,  Absinthium.  This  criterion  separates  a  natural  group 
of  the  species,  although  it  is  probably  not  of  sufficient  importance  to  be  rated  as  a 
sectional  character.  The  fact  that  the  pubescence  is  easily  determined,  and  that  in 
this  section  it  is  very  long  and  copious,  while  it  is  entirely  wanting  throughout  the  rest 
of  the  genus,  leads  to  the  retention  of  Absinthium  largely  because  of  practical  consid- 
erations. The  corollas  and  achenes  are  all  long-pubescent  in  spinescens,  and  this 
character  here  seems  to  attain  specific  importance.  However,  in  one  subspecies  of  A. 
tridentata,  namely,  parishi,  the  achene  is  long-pubescent,  although  no  other  characters 
can  be  found  which  run  parallel  with  this  one.  A  suggested  explanation  is  that  parishi 
has  arisen  through  mutation  in  this  single  character.  Aside  from  the  rather  pronounced 
pubescence  just  under  consideration,  there  are  sometimes  a  few  prominent  hairs  on  the 
upper  part  of  the  corolla.  These  are  frequently  described  in  species  of  the  Old  World, 
but  their  presence  or  absence  seldom  runs  parallel  with  other  characters.  Such  hairs 
are  occasionally  found  in  American  plants,  especially  in  forms  of  A.  norvegica  and  in 
A.  palter soni.  They  furnish  a  nearly  but  not  quite  constant  criterion  for  the  recognition 
of  the  latter  species  as  distinct  from  A.  scopulorum.  In  A.  norvegica  saxatilis  the  corolla- 
tube  is  perhaps  always  long-hairy. 

Resins,  oils,  and  odors. — Resins  are  not  copiously  developed  in  Artemisia  and  no 
species  is  marked  by  impressed  resin-dots  of  the  foliage.  There  is,  however,  a  prominent 
exudation  of  resin  on  some  parts,  particularly  on  the  flowers  and  achenes.  These 
resin-dots  harden  and  become  somewhat  granular.  Since  they  are  more  noticeable  in 
some  species  than  in  others,  it  may  be  that  their  presence  affords  contributory  evidence 
as  to  the  standing  of  certain  forms,  but  their  use  would  require  much  more  detailed  studies 
than  have  as  yet  been  given  to  them.  The  oils  are  abundant  in  some  species  and  give 
quite  characteristic  odors  to  the  herbage  in  these  cases.  For  this  reason,  the  odor  of 
the  herbage  in  each  of  the  species  is  mentioned  in  the  present  monograph,  although  it 
is  recognized  that  such  descriptions  do  not  carry  a  clear  conception  of  actual  conditions. 
It  is  only  by  extended  observation  in  the  field  that  one  can  come  to  recognize  the  different 
sorts  by  odor  alone. 

Habit. — All  degrees  of  duration  are  found  in  the  genus,  from  annual  herbs  to  arbores- 
cent, tree-like  perennials.     The  annual  and  biennial  plants  have  a  definite  taproot,  but 


44  GENUS   ARTEMISIA. 

the  transition  from  annual  to  biennial  habit  is  so  often  dependent  upon  ecologic  con- 
ditions that  this  character  is  of  but  slight  importance.  There  are  certain  places  in  the 
genus,  however,  where  only  annual  and  biennial  species  are  found,  while  in  other  sections 
plants  of  short  duration  are  not  known  to  occur.  A  great  majority  of  the  American 
species  are  perennial  herbs,  growing  either  from  rootstocks  or  from  a  caudex  that  sup- 
ports a  number  of  stems.  The  underground  structures  have  not  been  examined  in 
detail  and  their  characters  have  been  used  but  slightly  in  classification.  The  caudex 
habit  is  often  an  extreme  form,  derived  from  a  rootstock,  the  stock  becoming  much 
shortened  and  the  stems  growing  in  close  proximity.  It  often  happens  that  within  a 
single  species  some  forms  will  have  extensively  creeping  rootstocks,  while  others  will 
have  a  short  caudex,  the  latter  usually  belonging  to  more  northerly  habitats.  In  almost 
all  cases  when  the  plant  is  an  herb  the  stem  is  simple  up  to  the  inflorescence. 

The  shrubby  habit  has  been  developed  at  three  different  places  in  the  genus,  or  at 
least  this  follows  if  the  present  classification  into  sections  is  a  natural  one.  However, 
the  largest  shrubs,  as  well  as  the  largest  number  of  shrubby  species,  are  found  in  the 
section  Seriphidium.  These  shrubs  show  considerable  variation  in  habit,  and  hence 
the  differences  are  not  sharp  enough  to  permit  of  their  use  as  specific  criteria.  The  size 
is  sometimes  helpful,  but  it  is  not  always  dependable.  For  example,  the  largest  shrub 
of  all  is  A.  tridentata,  the  most  common  of  the  sagebrushes,  yet  even  in  subspecies  typica 
of  this  are  found  forms  sometimes  less  than  1  dm.  high.  Such  reduced  forms  are  often 
easily  accounted  for  by  field  studies  in  that  they  are  due  to  unfavorable  environmental 
conditions,  usually  to  competition,  especially  with  perennial  grasses,  or  to  continuous 
browsing,  to  fire,  to  poor  soil,  or  to  a  combination  of  all  of  these  factors.  One  of  the 
American  species  of  shrubs  stands  out  very  sharply  from  all  the  rest  by  its  decidedly 
spiny  habit.  This  is  A.  spinescens,  a  species  which  is  well  set  off  also  by  important 
floral  characters. 

RELATIVE  PLASTICITY  OF  THE  SPECIES. 

The  genus  Artemisia  includes  species  representing  nearly  all  degrees  of  plasticity. 
Some  are  in  a  state  of  constant  and  extensive  variation,  and  by  means  of  their  numerous 
forms  are  enabled  to  occupy  very  unlike  habitats.  Such  species  come  naturally  to  have 
a  wide  geographic  distribution  and  also  a  wide  altitudinal  range  in  mountainous  districts. 
While  their  forms  are  difficult  to  treat  taxonomically,  because  of  this  large  number  and 
the  striking  dissimilarity  of  the  extremes,  the  determination  of  the  evolutionary  lines 
is  rendered  fairly  certain  because  of  the  presence  of  intermediate  forms  and  the  compara- 
tive ease  of  manipulation  in  experimental  studies.  The  most  notable  species  of  this 
class  is  A.  vulgaris.  This  ranges  almost  throughout  the  temperate  and  subarctic  portions 
of  the  Northern  Hemisphere  and  comprises  an  almost  endless  series  of  variations,  some 
65  of  which  have  been  described  as  distinct  species  by  various  authors.  It  seems  quite 
probable  that  some  are  now  fixed  in  their  principal  characters  and  that  they  are  limited 
to  particular  habitats  in  consequence,  but  that  many  are  still  in  a  state  of  flux,  at  least 
in  some  portion  of  their  range. 

Other  species  which  are  represented  by  more  than  the  average  number  of  forms  are 
norvegica,  campestris,  dracunculus,  and  tridentata.  The.'^e  do  not  possess  the  high  plas- 
ticity of  vulgaris,  but  each  is  represented  by  15  or  more  named  variads  in  addition  to 
many  minor  forms.     All  are  of  wide  distribution  and  have  also  a  large  altitudinal  range. 

Of  the  less  plastic  species,  only  A.  frigida  is  of  wide  distribution.  It  has  but  few 
named  variations  in  America,  but  a  considerable  number  of  them  in  Asia.  A  few  intro- 
duced species  are  not  here  taken  into  account,  since  in  each  case  the  American  plants 
have  in  all  probability  descended  from  one  genetic  strain.  The  remaining  species,  such 
as  spinescens,  parryi,  franserioides,  pedatifida,  etc.,  are  all  rare  or  local,  or  confined  to 


DIAGNOSIS.  45 

peculiar  habitats.     In  these,  experiment  alone  can  determine  whether  their  stability- 
is  germinal  or  due  to  constant  environic  relations. 

In  reviewing  these  lists  it  will  be  noted  that  the  mobile  species  are  not  confined  to 
any  one  section,  but  that  they  are  well  distributed  throughout  the  genus.  It  is  apparent 
that  in  each  section  one  or  two  species  have  assumed  the  lead  and  by  reason  of  their 
high  plasticity  have  been  able  so  to  accommodate  themselves  to  a  wide  variety  of 
environmental  impacts  that  related  species  have  been  largely  excluded  from  extensive 
areas.  Whether  favorable  initial  conditions  have  led  to  greater  variation  in  some 
species  than  in  others,  or  whether  the  difference  in  the  number  of  forms  produced  by 
various  species  is  due  to  an  inherent  difference  in  their  plasticity,  is  an  interesting 
problem  that  scarcely  falls  within  the  scope  of  the  present  paper. 

GENERIC  DIAGNOSIS. 
ARTEMISIA  Linnaeus,  Sp.  PI.  845,  1753. 

Annual  and  perennial  herbs  and  shrubs,  usually  aromatic  and  bitter.  Roots  fibrous, 
the  annual  species  with  a  taproot,  the  perennial  herbs  often  with  rootstocks  or  caudex. 
Leaves  alternate,  entire  to  variously  lobed  or  dissected.  Heads  small,  nodding  or 
erect,  commonly  panicled  but  the  panicle  sometimes  much  reduced  and  then  raceme- 
like, spike-like  or  globoid,  apparently  discoid  but  the  marginal  flowers  with  irregular 
corollas  except  in  one  section  where  the  flowers  have  been  suppressed.  Involucre  ovoid  to 
campanulate  or  hemispheric;  bracts  imbricated  in  2  to  4  series,  dry,  at  least  the  inner 
ones  scarious  or  with  scarious  margins.  Receptacle  plane,  convex  or  hemispheric,  naked 
or  hairy  or  rarely  chaffy.  Ray-flowers  pistillate  and  fertile  or  wanting;  corollas  narrowly 
tubular,  usually  tapering  upwards,  with  2,  3,  or  4  teeth,  commonly  oblique  at  orifice; 
stamens  wanting;  style  more  or  less  exserted,  2-cleft,  the  branches  terete  to  oblong  and 
somewhat  flattened.  Disk-flowers  hermaphrodite,  fertile  or  sterile;  corollas  campanu- 
late, funnelform  or  trumpet-shaped,  regular,  5-toothed;  anthers  longer  than  the  fila- 
ments, obtuse  or  subcordate  at  base,  the  connective  produced  into  a  lanceolate  or  subu- 
late tip ;  style  exserted  or  sometimes  included,  cleft  into  2  more  or  less  recurved  branches 
which  are  flat,  truncate,  and  erose  or  fimbriate  at  the  end,  or  the  branches  more  or  less 
fused  into  a  slender  column  surmounted  by  an  erose  or  fimbriate  disk  or  cup.  Achenes 
in  both  ray  and  disk  ellipsoid  or  obovoid  to  nearly  prismatic,  with  2  to  5  angles  or  ribs 
or  with  numerous  faint  striae,  or  smooth,  usually  glabrous,  rounded  at  summit  to  an 
epigynous  disk,  or  truncate,  or  crowned  with  a  very  short  annulus.     Pappus  none. 


«>  GENUS   ARTEMISIA. 

Key  to  the  Sections  of  Artemisia. 
Heads  heterogamous,  marginal  flowers  pistUlate,  disk-flowers  hermaphrodite- 
receptacle  glabrous  or  pubescent.  ' 

Disk-nowers  fertile,  ovary  normal. 

Receptacle  not  hairy o„„_,„„     j     ak.  i  /      ..o\ 

Receptacle  beset  with  numerous  long  hairs  between  disk-flowers; .•.•:;:  Son   H    M^n^Zt  & 

Ho  P't'^-flo^ers  sterile,  ovary  abortive;  receptacle  glabrous Sect  on  III    DracuncX  Fd  47i 

Heads  homogamous  by  complete  reduction  of  ray-flowers,  disk-flowers  aU  her-  ^^''"°''^''-  ^'^'^^riculm  (p.  47). 

maphrodite  and  fertile;  receptacle  glabrous Section  IV.  Seriphidium  (p.  47). 

Key  to  the  North  American  Species  of  Artemisia. 
Section  1.  Abrotanum. 
(Ray-flowers  present,  disk-flowers  present  and  fertile,  receptacle  glabrous.) 
Heads  with  more  than  10  flowers;  leaves  never  cuneate  and  3-toothed  at  apex,  although 
5.  ,     , ,       sometimes  spatulate  and  3-cleft  or  3-lobed.    Herbs  and  shrubs 

Stems  woody  (decidedly  so  m  the  only  native  species,  less  woody  m  the  2  intro- 
duced   ones);    leaves    mostly    dissected    into    fiUform    lobes- 
„  .     .     ,  ,  achenes  angled,  broad  and  truncate  at  summit. 

Pnncipal  leaves  2  or  3  times  pinnatifid.     Introduced  species. 

Leaves  3  to  6  cm.  long,  lobes  slender,  ascending;  petiole  naked 1    A  abrotanum  fn  4ql 

Leaves  1  to  3  cm.  long,  lobes  short,  spreadmg;  petiole  auricled  at  base.  . .  2    A  Znti<T(^  %)     '' 

Pnncipal  leaves  mostly  once  pinnatifid.     Native  species 3    J  Sfo^i^  (n   m 

Stems  herbaceous,  sometimes  a  Uttle  woody  at  base;  leaves  entire  or  variously  cut  ""''J^^'^  (P-  53). 

but  seldom  with  truly  filiform  lobes;  achenes  smooth  or  ribbed 
™     .  .  ,     ,Dut  scarcely  angled,  mostly  with  slight  incurving  at  summit. 

i-lant  perennial,  stems  from  a  rootstock  or  caudex;  leaves  various 
Foliage    not   tomentose   beneath  but  silvery-canescent,  villous,  or  glabrous- 
stems  6  dm.  or  less  high.     Subalpine  and  Arctic  plants  with 
dissected  leaves. 
Disk-coroUas  2.5  to  3.5  mm.  long  (smaller  in  some  forms  of  No.  4);  heads  5 
to  9  mm.  broad,  except  in  senjavinensis  and  norvegica  glomerata 
begments  of  leaves  strongly  divergent,  primary  divisions  at  right-angles  to 

Segments  of  leaves  pointing  forward ^-  ^-  ""^"^^^^^  (P-  56). 

Leaf-lobes  longer   than   their  hairs,   or  leaves  glabrous;   lower  leaves 

usually  2  or  3  times  cleft  or  divided 5    ^   norveoica  (r,    'i7^ 

Leaf-lobes  exceeded  and  neariy  concealed  by  their  long  villous  pub^l  '      '  """^^"^  ^P"  ^'^- 

Disk-corollas  (p.  t  "^t^^t^^^"^-^..^  '  Southem'  Rocky     '^  ^^  ''""""^-^  '^^  '''■ 

„  ,  Mountains 7    A    t^tt,,,-  Cr,  fifi^ 

Fohagemoreorlesstomentosebeneath, usually denselyso;stems3to30dm"  high  ^' 

Disk-coroUas  3.5  to  4  mm.  long;  involucre  6  to  7  mm.   high.     A  white- 
Disk  rornlI«,  ^°"f  "^"'^  ''^'i'^  "^'^^  ^^7  large  heads  and  thick  obtuse  leaf-lobes.     8.  A.  stelleriana  (p.  67). 
uisk-corolias  1.5  to  3  mm.  long;  involucre  2.5  to  5  mm.  high 

Leaves  (except  the  uppermost)  twice  dissected  and  lobes  obtuse;  disk-flowers 
45  to  90. 

Heads  not  secund;  leaf-lobes  linear;  involucre  5  mm.  high 9.  ^  alaskana  (d  68) 

Heads  '^ec^'^ld^y^secund;  leaf-lobes  elliptic  or  oblanceolate;  involucre  2.5  '"°««»"<'  ^P-  ^SJ- 

Leaves  vari£usl£cutj-^entire  but  lobes  always  acute;  isk-flow'e^^  ^°'  ^- ■^^'""*^''^"  (P-  69)- 

Plant  annual  or  biennial,  with  taproot;  stem  erect;  leaves  2  or  3  times  pinnateiy  "'  ^'  "^""^  ^^'  ^^^' 
parted  or  divided.  -^ 

Leaves  green;  divisions  not  filiform. 

Involucre  2  to  3  mm.  high;  inflorescence  a  dense  compound  spike;  heads 

crowded,  erect 12    ,4    hi^r,i,  Cn   ini  ^ 

Involucre  1  to^^^S^mm.  high;  inflorescence  a  loose  panicle;'  heads  ioose;  often  ^^'      ^■ 

Heads  ^'tronTv"2';nTfl"!°"?'^i^'^*°°'?i^°T^--     Mexicanspecies  with  dense  panicies".  U.  1  IZZhFan^^fl  103). 
Heads  with  only  2  to  4  flowers;  leaves  at  least  m  part  cuneate  and  3-toothed  at  sum- 

mit.    Low  shrub 15_4_  bi^.^^.  (p  j^^j 

Section  II.  Absinthium. 
(Ray-flowers  present,  disk-flowers  present  and  fertile;  receptacle  villous.) 
Stem  4  to  10  dm.  high;  divisions  of  leaves  oblong  or  oblanceolate,  ultimate  segments 

'1>Tan\*;o'  r-  Y^  frf'/^^iell'er.inear,- ultimate-segments  about  1  mm!  wide.  ''^  ^^  ""'"''''''''^  '^^  ''''■ 

solitary. 
Heads  5  to  25,  4  to^6  mm.  broad;  disk-flowers  15  to  30;  leaves  mostly  twice  pin- 
Heads  1  to  5,  5  to  7mm.  broad;  ■disk:flowers30  to' 120;  leavesonce  pinnateiy  divided  ^^-  ^"  '"^^P^"™'"  (P-  "o>- 

°'  ^'^f* 19.  A.  pattersoni  (p.  112). 


KEY  TO  SPECIES.  47 

Key  to  the  North  American  Species  of  Artemisia — Continued. 
Section  III.  Dracuncclus. 
(Ray-flowers  present,  disk-flowers  present  but  sterile,  their  achenes  aborted;  receptacle  glabrous.) 
Plant  herbaceous,  stems  sometimes  a  little  woody  at  base;  heads  more  than   15- 
flowered  (including  both  ray-  and  disk-flowers). 
Leaves  mostly  entire  but  occasionally  with  an  irregular  lobe  or  lower  leaves  some- 
times 3-  to  5-cleft 20.  A.  dracunculus  (p.  115). 

Leaves  pinnatifid,  bipinnatifid,  or  dissected,  except  the  uppermost. 

Disk-corollas  campanulate,  1.5  to  3  mm.  long;  lower  leaves  2  to  10  cm.  long 

including  petiole;  inflorescence  1  to  10  cm.  broad 21.  A.  campestris  (p.  120). 

Disk-corollas  tubular-funnelform,  3  to  3.5  mm.  long;  lower  leaves  rarely  over  2 

cm.  long  including  petiole;  inflorescence  about  0.5  cm.  broad. .  23.  A.  pedatifida  (p.  131). 
Plant  shrubby  but  sometimes  dwarfed;  heads  less  than  15-flowered. 
Achenes  and  corollas  glabrous  or  only  minutely  pubescent;  plant  not  spinescent. 
Inflorescence  loosely  paniculate;  involucre  about  1.5  to  2  mm.  high;  disk-corollas 

2  mm.  or  less  long;  shrub  normally  3  to  10  dm.  high 22.  A.  filifolia  (p.  130). 

Inflorescence  spike-like;  involucre  about  3  mm.  high;  disk-corollas  3  to  3.5  mm. 

long;  shrub  dwarf  (1.5  dm.  or  less  high) 23.  A.  pedatifida  (p.  131). 

Achenes  and  corollas  cobwebby  with  long  hairs;  plant  spinescent 24.  A.  spinescens  (p.  132). 

Section  IV.  Seriphidium. 
(Ray-flowers  wanting,  disk-flowers  present  and  fertile;  receptacle  glabrous.) 
Receptacle  not  chaffy;  leaves  tomentose  on  both  sides,  except  in  pygmaea  and  one 
subspecies  of  tridentala. 
Leaves  gray,  wholly  covered  with  a  canescent  or  silvery  tomentum,  either  entire 
or  palmately  toothed,  cleft,  or  parted. 
Heads  in  spikes  or  panicles,  at  least  the  upper  ones  longer  than  their  subtending 
bracts. 
Leaves  (except  the  uppermost  entire  ones)  cuneate  to  spatulate-linear  in  outline, 

mostly  toothed  or  parted 25.  A.  tridentala  (p.  135). 

Leaves  hnear,  somewhat  tapering  to  each  end,  all  entire  or  rarely  with  a  few 

teeth  or  lobes,  silvery-canescent 26.  A.  cana  (p.  150). 

Heads  sessile  in  axils,  all  much  exceeded  by  their  subtending  leaves;  divisions  of 

leaves  linear,  mostly  5  to  15  mm.  long,  silvery 27.  A.  rigida  (p.  153). 

Leaves  green,  glandular-puberulent,  lower  pinnatifid  with  5  to  7  lobes 28.  .4.  pygmaea  (p.  154). 

Receptacle  chaffy  with  scarious  bracts  which  subtend  most  of  the  flowers;  leaves 

green  above,  tomentose  beneath 29.  A.  palmeri  (p.  155). 

Artificial  Key  to  the  North  American  Species  of  Artemisia. 
Plant  an  herb,  stems  often  thickened  and  perennial  at  base  but  never  decidedly  woody. 
Duration  annual  or  biennial;  plant  with  a  taproot. 

Inflorescence'  spike-like  but  in  reality  composed  of  a  series  of  short  spikes 12.  A.  biennis  (p.  101). 

Inflorescence  a  panicle. 

Leaves  gray,  densely  hairy,  lobes  thread-hke.     Mexico 14.  A.  klotzschiana  (p.  103). 

Leaves  green,  glabrous  or  sparsely  hairy  when  mature,  plane. 

Achenes  all  well  formed  and  fertile 13.  A.  annua  (p.  102). 

Achenes  of  central  flowers  aborted  and  sterile  (subspecies  caudata  of) 21.  A.  campestris  (p.  120). 

Duration  perennial;  plant  with  branching  crown  or  with  rootstocks. 
Segments  of  leaves  mostly  2  mm.  or  more  wide,  hnear  to  lanceolate  or  ovate,  or 
leaves  entire  and  over  2  mm.  wide. 
Lobes  of  leaves  obtuse. 

Involucre  6  to  7  mm.  high;  corolla  of  disk-flowers  3.5  to  4  mm.  long 8.  A.  stelleriana  (p.  67). 

Involucre  2.5  to  5  mm.  high;  corolla  of  disk-flowers  1.5  to  2.5  mm.  long. 
Receptacle  without  hairs  between  flowers.     Native. 

Heads  growing  from  both  sides  of  branch  (not  secund).    Alaskan  species.     9.  A.  alaskana  (p.  68). 
Heads  growing  from  only  one  side  of  branch  (secund).     Southwestern 

United  States 10.  A.  franserioides  (p.  69) . 

Receptacle  densely  long-hairy  between  flowers.     Introduced 16.  A.  absinthium  (p.  106). 

Lobes  of  leaves  acute,  or  leaf  itself  acute  if  not  lobed. 

Leaves  with  a  dense  tomentose  or  woolly  pubescence,  at  least  beneath 11.  .4.  vulgaris  (p.  71). 

Leaves  with  silky  or  spreading  pubescence  or  glabrous. 

Central  flowers  with  normal  achenes;  leaves  mostly  pinnatifid  or  cleft 5.  A.  norvegica  (p.  57). 

Central  flowers  without  achenes;  leaves  mostly  entire  or  with  few  lobes.  .  .   20.  A.  dracunculus  (p.  115). 
Segments  of  leaves  mostly  1  mm.  or  less  wide,  linear  or  fiUform,  rarely  eUiptic 
or  ovate  in  dwarf  plants,  or  leaves  entire  and  less  than  2  mm. 
wide. 
Receptacle  not  evidently  hairy  between  flowers. 
Leaves  mostly  entire,  a  few  cleft  into  2  or  3  short  ascending  lobes,  green.  ...  20.  A.  dracunculus  (p.  115) 
Leaves  pinnatifid  into  5  to  10  or  more  spreading  divisions. 

Achenes  present  only  in  marginal  flowers,  those  of  central  flowers  wanting.     21.  A.  campestris  (p.  120). 
Achenes  present  in  all  flowers. 

Foliage    tomentose    or    woolly,    especially    beneath;    leaf-lobes    linear- 
filiform  (mostly  subspecies  wrighti  of) 11.  A.  vulgaris  (p.  71). 

'  Throughout  this  key  the  term  inflorescence  is  used  to  indicate  the  assemblage  of  heads.     Strictly  speaking,  each  head 
is  an  inflorescence  in  itself. 


48  GENUS   ARTEMISIA. 

Artificial  Key  to  the  North  American  Species  of  Artemisia— Continued. 
Foliage  silky-pubescent  to  glabrous,  never  woolly  or  tomentose;  leaf- 
lobes  lanceolate  or  elliptic. 
Disk-corollas  2.5  mm.  or  more  long  (rarely  shorter  in  the  Alaskan 
macrobotrys). 

Segments  of  leaves  strongly  divergent 4.  A.  macrobotrys  (p.  56). 

Segments  of  leaves  pointing  forward. 

Leaf-lobes  not  concealed  by  their  hairs 5.  A.  norvegica  (p.  57). 

Leaf-lobes  entirely  hidden  among  their  long  villous  hairs Q.  A.  senjavinensis  (p.  65). 

Disk-corollas  2  mm.  or  less  long.     Southern  Rocky  Mountains 7.  A.  parryi  (p.  66). 

Receptacle  densely  long-hairy  between  the  flowers. 

Stems  very  leafy;  heads  usually  in  panicles.     Middle  and  lower  altitudes. ...    17.  A.  frigida  (p.  108). 
Stems  sparsely  leafy;  heads  in  racemes  or  solitary.     Alpine  and  subalpine. 

Heads  5  to  25;  leaves  mostly  twice  pinnatifid 18.  A.  scxipulorxim  (p.  110). 

Heads  1  to  4;  leaves  only  once  pinnatifid  or  cleft 19.  A.  pattersoni  (p.  112). 

Plant  a  shrub,  sometimes  low  but  always  decidedly  woody  at  base. 
Leaves  (except  sometimes  the  uppermost  ones)  pinnately  lobed  or  pinnatifid,  ulti- 
mate divisions  mostly  linear. 
Lobes  of  at  least  most  of  leaves  again  divided  or  dissected. 
Receptacle  not  hairy. 

Inflorescence  a  panicle;  leaves  twice  pinnatifid.     Introduced. 

Leaves  green  above 1.  A.  abrotanum  (p.  49). 

Leaves  white  on  both  sides 2.  A.  pontica  (p.  52). 

Inflorescence  raoerae-like;  leaf-divisions  ternately  cleft.     Alaskan 9.  A.  alaskana  (p.  68). 

Receptacle  thickly  beset  with  long  woolly  hairs  between  flowers. 

Plant  5  to  10  dm.  high;  divisions  of  leaves  lanceolate.     Introduced    16.  A.  absinthium  (p.  106). 

Plant  1  to  4  dm.  high;  divisions  of  leaves  narrowly  linear.     Native 17.  A.  frigida  (p.  108). 

Lobes  of  leaves  mostly  entire. 

Central  flowers  without  subtending  bracts. 

Fohage  gray  with  a  close  pubescence.     Coastal  shrub  5  to  25  dm.  high 3.  A.  calif ornica  (p.  53). 

Foliage  green,  glandular;  dwarf  plant  of  the  Great  Basin 28.  A.  pygmaea  (p.  154). 

Central  flowers  mostly  subtended  by  conspicuous  bracts  of  receptacle.     Large, 

coastal  plant 29.  A.  palmeri  (p.  155). 

Leaves  either  entire  or  palmately  toothed  or  cleft  from  summit. 

Shrub  very  spiny;  corollas  copiously  long-hairy 24.  A.  spinescens  (p.  132). 

Shrub  not  spiny;  corollas  not  hairy. 

Principal  leaves  entire  or  rarely  with  a  few  teeth  or  lobes,  linear,  somewhat 

tapering  to  each  end 26.  A.  cana  (p.  150). 

Principal  leaves  (that  is,  all  but  uppermost  entire  ones)  toothed  or  cleft  or 
parted  at  summit  (often  spatulate  or  fihform). 
Lobes  or  teeth  of  leaf  plane,  not  filiform  or  thread-like. 

Inflorescence  a  spike,  raceme,  or  panicle  with  at  least  upper  heads  longer 
than  their  subtending  bracts. 
Heads  in  panicles;  shrub  1  to  20  dm.  high;  leaves  toothed  or  cleft  but 
never  more  than  halfway  down. 

Panicles  loosely  branched;  flowers  all  alike  in  the  head 25.  A.  tridentala  (p.  135). 

Panicles  closely  branched,  heads  glomerate;  corollas  of  outer  flowers 
much  reduced  and  without  stamens.  Southern  Rocky  Moun- 
tains      15.  A.  bigelovi  (p.  104). 

Heads  in  racemes;  shrub  0.5  to  1.5  dm.  high;  leaves  divided  nearly  to 

base  into  usually  3  lobes 23.  A.  pedalifiAa  (p.  131). 

Inflorescence  consisting  of  solitary  heads  sessile  in  the  axils,  all  much 

exceeded  by  their  subtending  bracts  or  leaves 27.  A.  rigida  (p.  153). 

Lobes  of  the  leaf  filiform  (thread-like). 

Achenes  narrow  at  summit;  heads  3-  to  9- flowered.     Nebraska  and  Texas 

to  Chihuahua  and  Nevada 22.  A.  filifolia  (p.  130). 

Achenes  broad  at  summit;  heads  20-  to  50-flowered.     Coast  of  Cahfomia 

and  Lower  Cahfomia 3.  A.  californica  (p.  53). 


A.    ABROTANUM.  4KI 

Section  I.    ABROTANUM. 

Phylogeny  of  the  Species. 

There  are  two  native  North  American  species  in  this  section  which  are  so  isolated 
phylogenetically  from  the  others  that  they  are  represented  on  the  chart  by  divergent 
lines  from  the  base.  One  of  these  is  A.  calif ornica.  This  is  similar  to  two  Old  World 
species  now  introduced  into  the  United  States,  A.  abrotanum  and  A.  pontica,  but  since 
the  connections  may  be  rather  remote  these  are  indicated  by  broken  lines.  The  other 
isolated  native  species  is  A.  bigelovi,  which  may  have  arisen  from  A.  calif  ornica,  but  is 
probably  of  more  ancient  lineage.  The  remaining  species  fall  into  three  natural  assem- 
blages, conveniently  referred  to  as  the  norvegica,  vulgaris,  and  biennis  groups. 

The  norvegica  group,  that  is,  those  species  inclosed  in  a  major  circle  at  the  left,  is 
certainly  of  boreal  origin,  norvegica  itself  having  a  more  or  less  continuous  distribution 
in  the  circumpolar  regions  of  Eurasia  and  North  America,  with  a  southward  extension 
into  the  Rocky  Mountains.  The  center  of  distribution  was  probably  in  Siberia,  the 
American  forms  coming  by  way  of  Alaska  and  thence  down  the  continent.  A.  parryi 
is  a  stranded  species  of  high  mountains  near  the  southern  limits  of  the  group,  while 
macrobotrys  and  senjavinensis  are  boreal  developments  that  do  not  extend  far  southward. 

The  vulgaris  group  is  not  inclosed  in  a  major  circle  on  the  chart  because  the  species 
are  not  so  closely  related  to  one  another  as  are  those  of  the  other  two  groups.  A.  vulgaris 
itself  is  of  wide  distribution  on  both  continents,  has  its  center  of  distribution  in  northern 
Asia,  and  has  a  fan-hke  distribution  in  North  America,  the  area  of  widest  extent  east 
and  west  being  in  the  United  States.  In  the  course  of  its  migrations  this  species  has 
adapted  itself  to  an  extensive  series  of  conditions,  and  an  enormous  number  of  minor 
variations  and  subspecies  has  resulted.  The  northern  broad-leaved,  large-headed  tilesi 
undoubtedly  represents  the  most  primitive  of  these,  since  the  others  exhibit  increasingly 
specialized  structures  when  arranged  in  the  order  of  their  southerly  and  easterly  distri- 
bution. The  other  species  of  the  vulgaris  group  are  stelleriana,  which  is  of  wide  distri- 
bution but  restricted  to  sandy  beaches;  alaskana,  a  little-known  species  of  the  far  north; 
and  franserioides,  which  apparently  is  a  relict  stranded  in  the  southern  Rocky  Mountains. 

The  biennis  group  comprises  three  species,  all  closely  related  and  characterized  by 
their  annual  or  at  most  biennial  habit.  Two  of  the  species  are  represented  also  in  Europe, 
and  since  none  of  them  occur  in  Arctic  regions,  it  seems  probable  that  they  have  reached 
America  by  way  of  the  North  Atlantic,  where  land  connections  may  have  been  more 
recent  than  across  the  Pacific,  or  it  may  be  that  the  introduction  was  even  more  direct. 
Whatever  the  route,  the  connection  is  an  old  one,  since  time  must  be  allowed  for  the 
later  evolution  of  the  peculiar  Mexican  A.  klotzschiana. 

The  evidence  upon  which  this  sketch  is  based  is  indicated  in  detail  in  the  paragraphs 
on  the  relationships  of  the  several  species. 

1.  ARTEMISIA  ABROTANUM  Linnaeus,  Sp.  PI.  845,  1753.     Plate  1.     Garden 
Sagebrush. 
A  shrub,  5  to  20  dm.  high,  pleasantly  scented;  stems  much  branched,  erect  or  some- 
what spreading,  forming  rounded  bushes,  the  twigs  erect,  prominently  striate,  glabrous, 
often  red  or  reddish  tinged;  principal  leaves  numerous,  petioled  (petiole  naked  at  base), 

3  to  6  cm.  long,  2  or  3  times  pinnately  dissected  into  ascending  linear-fiUform  divisions 
with  revolute  margins,  green,  glabrous  or  sparsely  puberulent  above,  Ughtly  tomentulose 
beneath;  upper  leaves  similar  but  smaller  and  some  only  once  pinnatifid  or  3-cleft  or 
entire;  inflorescence  an  elongated  terminal  panicle,  leafy  below,  15  to  40  cm.  long, 

4  to  15  cm.  broad;  heads  heterogamous,  short-peduncled,  nodding;  involucre  hemispheric 
or  subglobose,  about  2  to  2.5  mm.  high,  2.5  to  3  mm.  broad  (involucres  somewhat  larger 
according  to  some  descriptions,  but  only  small-headed  forms  thus  far  seen) ;  bracts  8  to 


50 


GENUS   ARTEMISIA. 


I  s.  g/asAana  j 


{/.  abrofanum  j  j    2.pon/-ica    j 

Lvs.3-6cm.long,      LvS.  i-3  cm.  long, 
lobes  siender.as-  lobes  short, 
cending;  petiole     spreading;  petiole, 
naked       \,    auricled  at  base 


Principal  lvs.2or3  principal  Ivs.mostly 
times  pmnatifid.  ..pinnatifld.  Native 
Introduced  species 


Shrubs;  achenes  broad 

and  truncate  at  summit, 

sharply  angled',  ray- f Is.  5-20. 

Lvs. dissected,  mostly  into  filiform  lobes 


Herbs; achenes 
narrowed  above 
to  a  small  epigyn- 
ous  disk,  not  ang- 
led; ray-fls.  4-15 
(or  more) 


Stirubj  achenes  narrowed 
above,  not  angled;  reduc- 
tion in  ray-fls.  to  3,2, on; 
Iv3.  3-dentate.  Connecting 
with  section  Ser/phidium, 


Fio.  4. —  Phylogenetic  chart  of  the  species  of  AHemiaia  Bection  Abrolan 


A.    ABROTANUM.  51 

18,  the  outer  ones  linear-lanceolate,  nearly  equaling  the  inner  ones,  with  herbaceous 
medial  line  and  broad  scarious  margins,  canescent  or  somewhat  tomentose,  the  rest 
broadly  elliptic,  mostly  scarious  and  less  pubescent;  receptacle  naked;  ray-flowers  5  to 
15,  corolla  about  1.5  mm.  long,  narrowed  upwards;  disk-flowers  10  to  20,  fertile,  corolla 
campanulate,  1.5  to  perhaps  2  mm.  long,  5-toothed,  glabrous;  style-branches  of  disk- 
flowers  flat,  truncate,  erose  at  summit;  achenes  nearly  oblong  but  broadest  at  the  truncate 
summit,  4-  or  5-angled,  glabrous. 

Southern  Europe  and  the  Orient ;  occasionally  escapes  from  gardens  in  North  America. 
Type  locality,  Syria.  Collections:  McDonough,  New  York,  July,  1886,  Coville  (US); 
Washington  Island,  Wisconsin,  September  13,  1889,  Schuette  (Gr);  Benson  County, 
North  Dakota,  August  3,  1913,  Lunell  (US);  Indian  Head,  Assiniboia,  Macoun  10986 
(NY). 

MINOR  VARIATIONS. 

Artemisia  procera  Willdenow,  Sp.  PI.  3:  1818,  1804.  European  and  Asiastic  botanists  have  almost  uni- 
versally treated  this  as  a  species  distinct  from  A.  ahrolanum,  but  the  two  are  so  closely  similar  in  all  essential 
characters  that  its  reduction  to  subspecific  rank  would  better  express  their  botanical  relationship.  It  is  less 
shrubby  than  this  species,  the  stems  are  said  to  be  more  decidedly  erect,  and  the  leaves  are  more  finely  dis- 
sected. The  involucre  is  described  as  only  subcanescent  or  even  glabrous  (Willdenow)  as  contrasted  with  the 
densely  cinereous  or  even  tomentose  involucre  of  ahrolanum,  but  apparently  all  degrees  of  density  of  pubescence 
occur.  A.  procera  was  collected  many  years  ago  at  Buffalo,  New  York,  by  Clinton,  and  was  said  then  to  be 
established  in  two  or  three  places  as  a  garden  escape.  A  number  of  varieties  are  recognized  in  the  Old  World, 
and  similar  forms  may  be  expected  in  ahrolanum.  These  are  based  upon  such  characters  as  the  shape  and 
size  of  the  head,  the  presence  or  absence  of  pubescence  on  the  corollas,  and  the  amount  of  odor.  Eight  of 
these  varieties  are  described  by  Besser  (in  De  Candolle,  Prodr.  6: 108,  1837). 

RELATIONSHIPS. 

This  common  Old  World  plant  has  given  its  name  to  the  section  Ahrolanum  and  with 
scarcely  a  doubt  is  one  of  the  most  primitive  species  of  the  genus.  This  conclusion  is 
based  upon  the  theory  that  the  other  sections  arose  from  this  one,  as  outlined  in  the 
chapter  on  subgenera  and  sections,  and  also  upon  the  shape  and  ribbing  of  the  achenes. 
These  achenial  characters  ally  abrotanum  with  pontica  and  californica,  as  is  set  forth 
under  the  latter  species  where  reasons  are  also  given  for  considering  this  the  most  primi- 
tive group  of  the  section. 

The  size  of  the  heads  and  flowers  and  the  number  of  the  latter  are  all  somewhat 
smaller  as  given  in  the  above  description  than  those  of  Rydberg  in  the  North  American 
Flora.  Our  figures  are  based  upon  10  sheets,  about  half  of  which  are  of  introduced 
plants,  the  remainder  being  European. 

ECOLOGY  AND  USES. 

The  life-form  of  Artemisia  abrotanum  is  that  of  the  shrub  or  bush,  resembling  A. 
californica.  Its  role  in  vegetation  appears  to  have  received  no  attention  in  its  native 
area.     In  America  the  species  is  cultivated  and  has  escaped  into  waste  places. 

In  old  English  gardens  especially,  but  also  in  American  gardens,  the  southernwood, 
or  old  man,  as  this  species  is  commonly  called,  is  much  grown  as  an  ornamental  shrub. 
Its  value  for  this  purpose  lies  in  its  strong  bushy  growth  and  in  the  pleasant  odor  of  the 
herbage.  At  the  Canada  experimental  farms  it  is  considered  as  the  best  shrub  for  wind- 
breaks, while  in  Colorado  it  has  been  used  as  a  nurse  crop  in  reforestation,  although  it 
there  kills  down  in  winter  and  so  is  of  only  temporary  use.  The  plants  are  easily  grown, 
both  from  seeds  and  from  cuttings  taken  in  early  summer,  and  thrive  in  any  ordinary 
garden  soil.  They  are  somewhat  tender  as  regards  cold,  but  are  grown  as  far  north  as 
the  Canadian  boundary  on  both  sides  of  the  continent.  The  leaves  have  a  pleasant  taste 
and  were  formerly  much  used  for  the  preparation  of  a  decoction  employed  as  a  tonic  and 
anthelmintic. 


52  GENUS   ARTEMISIA. 

2.  ARTEMISIA  PONTICA  Linnaeus,  Sp.  PL  847,  1753.     Plate  1.    Roman  Wormwood. 

A  perennial  herb  with  a  slightly  woody  base  and  creeping  rootstock,  3  to  10  dm. 
high,  the  herbage  fragrant;  stems  unbranched  for  most  of  their  length,  erect,  striate, 
Ughtly  puberulent,  glabrate  and  then  commonly  reddish;  principal  leaves  crowded, 
petioled  (the  petiole  with  stipule-like  often  lobed  auricles  at  base),  1  to  3  cm.  long,  twice 
pinnatifid  into  short  divergent  linear  divisions,  these  often  toothed,  the  margins  obscurely 
revolute,  tomentulose  but  sometimes  glabrate  above,  densely  tomentulose  beneath; 
upper  leaves  similar  but  smaller,  the  uppermost  sessile  and  less  divided  or  only  ternately 
cleft  or  entire;  inflorescence  a  terminal  panicle,  leafy  below,  10  to  25  cm.  long,  2  to  4  cm. 
broad;  heads  heterogamous,  short-peduncled,  nodding  or  at  least  spreading  on  the 
raceme-like  branches;  involucre  hemispheric,  about  2  to  3  mm.  high,  3  to  4  mm.  broad; 
bracts  12  to  18,  the  outermost  ones  lanceolate,  herbaceous,  densely  tomentulose,  slightly 
shorter  than  the  others,  the  inner  ones  obovate  or  broadly  elliptic,  mostly  scarious,  tomen- 
tulose only  where  exposed;  receptacle  naked;  ray-flowers  10  to  15  or  18,  corolla  about  1 
mm.  long,  narrowly  tubular,  rather  deeply  toothed;  disk-flowers  25  to  45,  fertile,  corolla 
campanulate,  1  to  1.5  mm.  long,  5-toothed,  glabrous;  style-branches  of  disk-flowers  flat, 
truncate,  erose  at  summit;  achenes  somewhat  turbinate,  with  broad  truncate  shoulder- 
like summit  which  often  forms  a  narrow  raised  border,  4-  or  5-angled,  glabrous. 

Eastern  Europe  and  adjacent  Asia;  escaped  from  cultivation  in  southern  Canada  and 
at  various  points  from  Maine  to  Pennsylvania  and  Ohio.  Type  locality,  Hungary. 
Collections:  Portland,  Maine,  Fernald  2213  (Or);  Walpole,  New  Hampshire,  Fernald  509 
(SF) ;  Southington,  Connecticut,  September  15, 1908,  Bissell  (Gr) ;  Point  Edward,  Ontario, 
Dodge  24  (US);  Gouverneur,  New  York,  Phelps  1218  (Gr);  Luzerne  County,  Pennsyl- 
vania, September  20,  1890,  Small  and  Heller  (US);  Milan,  Erie  County,  Ohio,  August 
20,  1914,  MacDaniels  (Gr). 

RELATIONSHIPS. 

The  closest  allies  of  A.  pontica  are  Old  World  species.  One  of  these,  namely  A. 
abrotanum,  occurs  also  in  America  as  an  introduced  plant.  The  evidence  of  the  close 
relationship  of  these  two  species  is  found  chiefly  in  the  achenes,  which  are  almost  identi- 
cal in  shape  and  angles  and  very  unlike  those  of  most  other  species.  The  evidence  at 
hand  indicates  that  pontica  is  the  more  highly  developed  of  the  two,  as  is  seen  in  its  more 
specialized  leaves  and  reduced  inflorescence.  It  is  not  unlikely  that  a  close  study  of  Old 
World  species  will  reveal  others  more  closely  allied  to  pontica.  The  nearest  American 
relative,  and  the  only  one  with  similar  achenial  characters,  is  A.  calif ornica,  under  which 
is  given  a  full  discussion  of  the  probable  origin  of  this  group. 

The  only  Artemisia  with  which  pontica  could  be  confused  in  this  country  is  A.  abro- 
tanum. From  this  it  differs  in  its  herbaceous  habit,  and  especially  in  the  shorter  leaves 
with  very  short  divergent  segments  and  with  a  pair  of  conspicuous  divided  lobes  at  the 
base  of  the  petiole.  The  young  foliage  is  quite  gray  or  almost  white  as  compared  with 
the  green  foliage  of  abrotanum,  and  the  flowers  are  smaller. 

ECOLOGY  AND  USES. 

Artemisia  pontica  is  a  perennial  herb  with  creeping  rootstock  and  sHghtly  woody 
base,  which  forms  open  societies  on  hillsides  and  open  places  in  central  and  southeastern 
Europe.     In  America  it  is  an  infrequent  escape  in  waste  places. 

The  gray  and  finely  dissected  leaves  give  to  this  plant  a  very  pleasing  appearance, 
and  it  is  therefore  in  some  use  as  a  garden  ornamental.  In  France  it  is  sometimes  pre- 
ferred to  A.  absinthium  in  the  preparation  of  absinthe,  but  it  is  not  much  used  for  this 
purpose.  It  has  also  found  some  use  as  a  substitute  for  southernwood  {A.  abrotanum) 
for  medical  purposes,  but  it  is  said  to  be  less  eflScacious. 


A.    CALIFORNICA. 


53 


3.  ARTEMISIA  CALIFORNICA  Leasing.  Linnaea  6  :  523, 1831.    Plate  2.    Coast 
Sagebrush. 

A  rounded  shrub  with  a  definite  woody  trunk,  5  to  15  or  rarely  25  dm.  high,  with  a 
strong  pungent  odor;  stems  several  or  numerous,  freely  branched,  the  older  parts  with 
a  brown  fibrous  bark,  the  twigs  mostly  erect,  stout,  striate,  gray  or  nearly  white  with  a 
close  canescent  pubescence;  principal  leaves  sessile  or  at  least  with  no  distinction  between 
blade  and  petiole,  2  to  5  or  rarely  10  cm.  long,  0.5  to  1  mm.  wide  below  the  lobes  or  1  to 
3  mm.  wide  in  insular  forms,  ternately  or  pinnately  or  rarely  bipinnately  divided  into 
long  segments  not  wider  than  the  rachis,  commonly  with  fascicled  ones  in  their  axils, 
minutely  but  densely  cinereous  or  canescent;  upper  and  fascicled  leaves  gradually 
reduced  in  size  upwards,  less  divided  or  entire,  pubescent  like  the  lower;  inflorescence 
racemose-paniculate,  leafy-bracteate  throughout,  10  to  30  cm.  long,  1  to  10  cm.  broad; 
heads  heterogamous,  peduncled,  nodding;  involucre  hemispheric,  2.5  to  4  mm.  high,  3  to 
5  mm.  broad;  bracts  12  to  20,  the  outer  ones  short,  thick,  and  herbaceous,  the  inner  ones 
with  thick  backs  and  broad  scarious  margins,  oblong  or  rhomboidal,  obtuse,  all  canescent 
on  the  exposed  parts;  receptacle  conic,  glabrous  (or  barely  pubescent);  ray-flowers  6  to 
10,  or  up  to  15  in  insular  forms,  corolla  tubular,  nearly  regular,  about  4-toothed,  1  mm. 
long;  disk-flowers  15  to  30,  or  30  to  40  in  insular  forms,  corolla  campanulate,  5-toothed, 
1.5  to  2  mm.  long,  glandular-granuliferous;  style  of  ray-flowers  2-cleft,  well  exserted,  of 
disk-flowers  2-cleft,  barely  exserted,  the  branches  truncate;  achenes  of  both  ray-  and 
disk-flowers  oblong-turbinate,  broad  and  truncate  at  summit,  with  a  slightly  raised,  often 
undulate  rim,  5-angled,  resinous-granuliferous. 

Abundant  on  exposed  slopes  of  low  hills  and  ranges  in  California  from  the  north 
side  of  San  Francisco  Bay  and  Mount  Diablo  to  San  Pedro  Martir  in  Lower  California; 
also  on  the  adjacent  islands  and  east  in  southern  California  to  the  borders  of  the  Colorado 
Desert.  Type  locality,  California.  Collections  (all  in  California  and  Lower  California) : 
Hills  just  east  of  Vallejo,  north  side  of  San  Pablo  Bay,  Hall;  Mare  Island,  north  side  of 
San  Francisco  Bay,  September  22,  1874,  Greene  (Gr);  type  collection,  San  Francisco, 
Chamisso  (Gr) ;  San  Antonio  Canon,  Black  Mountain,  Santa  Cruz  Mountains,  Abrams  8 
(US,  minor  variation  4,  A.foliosa  Nuttall);  Pacific  Grove,  Heller  7198  (DS,  Gr,  NY,  UC, 
US);  near  Santa  Barbara,  Eastwood  U5  (Gr,  NY,  UC,  US);  Avalon,  Santa  Catalina 
Island,  January  1901,  Trask  (NY,  US,  minor  variation  4,  A.foliosa  Nuttall) ;  Pot's  Trail, 
San  Clemente  Island,  Trask  286  (NY,  US,  type  collection  of  Crossostephium  insulare 
Rydberg,  minor  variation  7);  San  Nicholas  Island,  Trask  71  silvery  and  71a  dun-colored 
(NY,  US,  same  variation);  Cabezon,  westerly  edge  of  Colorado  Desert,  October  15, 
1904,  and  October  24,  1907,  Bailey  (UC,  minor  variation  4,  A.  foliosa  Nuttall);  Las 
Huevitas,  near  San  Rosario,  Lower  California,  May  1889,  Brandegee  (UC) ;  Guadalupe 
Island,  Franceschi  11  (UC). 

MINOR  VARIATIONS  AND  SYNONYMS. 

This  species  is  fairly  constant  in  its  botanical  characters,  due  in  part  to  an  almost  continuous  distribution 
throughout  its  range  and  perhaps  also  to  its  isolation  phylogenetically  from  its  nearest  allies.  The  only  varia- 
tion of  more  than  passing  interest  is  No.  7  of  the  following  list. 

1.  Artemisia  abrotanoides  Nuttall,  Trans.  Am.  Phil.  Soc.  II.  7  :  399,  1841.  Described  from  specimens 
collected  near  Santa  Barbara  with  no  reference  to  the  earlier  ccUifornica,  for  which  it  is  an  exact  synonym. 

2.  A.  nscHERiANA  Besser,  Nouv.  Mem.  Soc.  Nat.  Mosc.  3  :  21,  1834.  Same  as  A.  califomica.  Type 
locality,  San  Francisco  Bay. 

3.  A.  FiscHERiANA  VEGETIOR  Bossef,  1.  c.  88,  Is  4.  colifomica. 

4.  A.  FOLIOSA  Nuttall,  1.  c.  397.  Recently  revived  by  Rydberg,  who  separates  it  on  the  basis  of  its  silvery- 
white  pubescence  and  the  mostly  ternately  cleft  leaves  with  very  narrow  segments.  These  distinctions  are 
impossible  to  apply  in  the  field  because  of  the  presence  of  all  grades  of  pubescence  and  type  of  leaf,  often  on  the 
same  or  closely  neighboring  plants.  Dwarfed  individuals  in  which  the  leaves  are  shortened  and  the  inflores- 
cence reduced  are  most  likely  to  exhibit  the  characters  oi  foliosa.  While  the  twigs  and  foliage  grade  insensibly 
in  color  from  the  common  gray  type  to  the  silvery- white  of  foliosa  in  the  coastal  districts,  according  to,  Vernon 
Bailey  these  two  color-forms  grow  together  at  Cabezon,  on  the  edge  of  the  Colorado  Desert,  and  intermediat  e 


54  GENUS   ARTEMISIA. 

are  there  absent.  The  extreme  development  of  the  white  form,  with  the  leaves  nearly  all  reduced  to  the  trifid 
type  and  with  numerous  gray,  brittle  twigs,  is  found  at  the  most  easterly  known  station  for  the  species,  namely 
7  km.  southeast  from  Palm  Springs  (February  1921,  Jaeger).  All  of  these  characters  are  in  line  with  the  general 
tendency  in  desert  vegetation.  The  ternately  cleft  nature  of  the  foliage  is  derived  from  the  pinnate  type,  as 
indicated  by  specimens  in  which  the  leaves  are  3-lobed,  but  with  one  lobe  attached  lower  down  than  the  others 
(130825  UC) ;  in  the  typical  form  some  of  the  leaves  are  often  only  ternately  cleft  or  bifid  at  the  summit  (29665 
UC  and  91195  UC),  while  others  are  irregularly  pinnatifid.  Some  of  these  leaf-forms  are  shown  on  the  accom- 
panying plate.     The  type  of  foliosa  came  from  around  Monterey. 

5.  Crossostephium  californicum  Rydberg,  N.  Am.  Fl.  34  :  243,  1916.     A.  californica. 

6.  C.  FOLiosuM  Rydberg,  1.  c.  ^.  californica,  the  form,  or  state,  referred  to  under  No.  4. 

7.  C.  INSUL.\RE  Rydberg,  1.  c.  244.  A  robust,  insular  variation  of  A.  californica  with  leaf-segments  1  to 
3  mm.  wide  and  not  revolute.  Thus  far  it  is  known  only  from  San  Clemente  and  San  Nicholas  Islands,  off  the 
coast  of  southern  California.  The  typical  form  also  grows  on  at  least  one  of  these  (San  Clemente  Island, 
March  25,  1918,  Evermann,  Calif.  Acad.  Sci.).  On  neighboring  islands  are  found  forms  intermediate  between 
the  type  of  californica  and  the  one  listed  above  as  foliosa.  The  remarkable  width  of  the  leaf-segments  and 
rachis  in  insidare  is  the  result  of  the  failure  of  the  margins  to  become  closely  revolute,  as  in  the  other  varia- 
tions. This  condition  is  approached  in  specimens  from  near  Santa  Monica,  on  the  mainland  nearly  opposite 
the  islands  on  which  insulare  grows.  In  these  the  leaf-margins  are  revolute  but  do  not  meet.  The  largest 
leaf-segments  are  1.5  mm.  wide  (near  Santa  Monica  Experiment  Station,  Barber  2S4,  UC).  Segments  up  to  1.8 
mm.  wide  occur  on  vigorous  shoots  from  as  far  north  as  the  Oakland  Hills.  Two  color-forms  occur  on  the 
islands,  both  with  the  wide  leaf-lobes,  so  that  if  foliosa  is  accepted  as  a  species,  or  variety,  it  will  be  necessary 
similarly  to  recognize  these  forms.    The  type  of  insulare  came  from  along  Pot's  Trail,  San  Clemente  Island. 

RELATIONSHIPS. 
There  has  been  a  wide  divergence  of  opinion  as  to  the  relationships  of  this  species. 
Both  Gray  and  Rydberg  have  assumed  a  close  connection  with  Crossostephium  artemi- 
sioides  Lessing  {Artemisia  chinensis  Vahl,  not  Linnaeus),  a  species  of  the  Philippine 
Islands  and  China.  The  former  author  would  therefore  unite  the  genus  Crossostephium 
with  Artemisia  (Syn.  Fl.  N.  Am.  P:370,  1884),  while  Rydberg  would  refer  californica, 
together  with  2  minor  segregates,  to  the  genus  Crossostephium  (N.  Am.  Fl.  34:243, 
1916).  The  bases  for  this  assumed  relationship  were  (1)  a  distinct  ribbing  of  the  disk- 
achenes  and  (2)  the  supposed  presence  of  a  coroniform  pappus,  two  characters  not  other- 
wise known  at  that  time  in  the  genus,  except  in  the  Hawaiian  A .  au^tralis  Lessing.  There 
can  be  no  question  as  to  the  ribbing  of  the  achenes  in  A.  californica.  In  mature  fruits 
these  ribs  take  the  form  of  5  sharp  angles;  3  and  4  ribs  are  included  in  descriptions  but  a 
careful  examination  of  numerous  collections  indicates  that  5  is  perhaps  the  universal 
number.  The  presence  of  these  angles  suggests  a  remote  connection,  through  forms 
now  extinct,  with  true  Crossostephium  of  southeastern  Asia,  but  further  evidence  is 
needed  in  support  of  the  hypothesis.  This  evidence  is  not  to  be  found  in  the  presence 
of  a  pappus  or  in  any  other  character  thus  far  pointed  out.  As  a  result  of  detailed 
studies  on  a  large  series  of  specimens,  the  conclusion  is  reached  that  the  Californian 
species  never  shows  any  evidence  of  a  true  pappus.  The  summit  of  the  achene  is  broad 
and  the  edges  commonly  curve  upward  to  form  a  shallow  cup  or  rim  about  the  base  of 
the  corolla-tube,  as  indicated  in  the  detailed  drawings  of  plate  2.  But  there  is  no  reason 
to  interpret  this  as  a  pappus-crown,  and,  in  fact,  it  is  no  more  prominent  than  in  some 
species  universally  accepted  as  genuine  Artemisias,  for  example,  A.  pontica  and  A. 
tridentata  (plates  1  and  18).  There  is  never  any  splitting  of  this  rim  nor  the  presence 
of  distinct  paleae  as  in  the  case  of  true  Crossostephium.  Furthermore,  this  monotypic 
genus  differs  decidedly  from  our  American  plants  in  the  presence  of  2  rows  of  ray-flowers, 
a  character  apparently  overlooked  both  by  Gray  and  by  Rydberg.  Although  A.  cali- 
fornica and  A.  australis  were  described  by  Lessing  in  the  same  volume  as  his  genus 
Crossostephium,  he  made  no  comparisons  with  this  last  and  presumably  had  no  thought 
of  their  relationship.  His  treatment,  which  considers  Crossostephium  as  a  monotypic 
genus  and  refers  californica  and  australis  to  Artemisia,  was  followed  by  Bentham  and 
Hooker  and  by  Hoffman  in  Engler  and  Prantl's  Pflanzenfamilien  and  is  the  one  which 


A.    CALIFORNICA.  55 

still  seems  the  most  reasonable.  Whether  or  not  the  angular  achenes  signify  a  remote 
connection  with  Crossostephium,  it  is  very  certain  that  nothing  is  gained  by  throwing 
californica  and  australis  into  this  genus  on  the  basis  of  a  single  character  and  in  the 
face  of  decided  differences  in  other  important  features. 

Much  more  direct  is  the  connection  between  A.  californica  and  two  Old  World  species, 
namely  A.  pontica  and  A.  abrotanum.  These  are  in  agreement  as  to  all  essential  features, 
even  down  to  the  angled  turbinate  disk-achenes  with  broad  shoulder-like  summits,  as  is 
shown  in  the  accompanying  plates.  Angled  achenes  are  encountered  at  a  number  of 
places  in  the  genus.  Sometimes  these  angles  are  reduced  to  ribs  which  pass  through 
all  degrees  of  depression  until  in  some  cases  the  surface  seems  to  be  perfectly  smooth 
(p.  37).  Since  the  characters  of  strongly  angled  and  crowned  achenes  are  approximated 
also  in  true  Crossostephium,  which  because  of  its  pappus  and  two  rows  of  ray-flowers 
may  be  accepted  as  still  more  primitive,  A.  pontica,  A.  abrotanum,  and  A.  californica 
(together  with  A.  australis)  may  well  represent  the  early  stock  from  which  the  other 
Artemisias  have  been  derived.  There  is  no  reason  to  assume,  however,  that  the  other 
species  have  arisen  from  these  as  they  now  exist,  for  although  primitive  in  most  of  their 
characters,  each  exhibits  special  development  along  certain  lines  and  all  are  shrubby 
in  habit.  This  demonstration  of  the  phylogenetic  connections  of  californica  and  similari- 
ties between  it  and  the  Hawaiian  A.  australis  render  more  plausible  the  theory  that  it 
has  had  some  geographic  connection,  perhaps  through  Asia,  with  the  primitive  Old 
World  stock,  as  now  represented  by  pontica  and  its  allies.  How  californica  came  to  be 
stranded  on  the  Pacific  coast  of  North  America  is  a  problem  that  can  not  now  be  solved, 
but  it  apparently  resulted  from  the  general  circumpolar  migration  of  the  genus. 

Among  the  native  American  representatives  of  the  section  Abrotanum,  Artemisia 
californica  stands  alone.  It  is  the  only  species,  except  for  the  anomalous  A.  bigelovi, 
which  is  shrubby  in  habit.  For  these  reasons  it  is  assigned  to  a  divergent  line  on  the 
phylogenetic  chart.  Whether  it  has  arisen  from  a  Crossostephium-like  ancestor,  or 
whether  of  some  other  origin,  its  early  segregation  seems  certain,  in  view  of  the  absence 
of  direct  connection  with  existing  species.  In  aspect  it  is  most  like  A.  filifolia,  which  it 
also  represents  ecologically  on  the  Pacific  Coast.  WhUe  it  is  not  impossible  that  these 
two  are  connected  phylogenetically,  the  difference  in  nearly  all  technical  characters 
seems  to  render  this  improbable. 

The  available  evidence  therefore  points  to  the  tentative  conclusion  that  A.  californica 
is  not  directly  related  to  any  other  American  species,  but  that  its  connections  are  with 
the  Hawaiian  A.  australis  and  with  certain  Old  World  species,  especially  A.  pontica 
and  A.  abrotanum.  Furthermore,  these  four  species  best  represent  the  early  stock 
of  Artemisia  and  hence  the  connection  with  the  genus  Crossostephium. 

ECOLOGY. 

In  life-form  Artemisia  californica  is  a  bush,  which  resembles  both  A.  filifolia  and 
A.  tridentata.  It  is  the  most  important  dominant  of  the  Coastal  sagebrush  association, 
extending  from  San  Francisco  Bay  to  the  Mojave  and  Colorado  Deserts,  and  blooming 
through  the  summer.  Typically,  it  is  a  climax  dominant,  but  it  is  often  subclimax  to 
the  chaparral  association  in  the  habitat  of  the  latter.  It  comes  in  contact  with  the  true 
sagebrush  of  the  Great  Basin  at  various  places  from  Tehachapi  Pass  south  to  Lower 
California,  and  the  two  not  infrequently  mingle  on  equal  terms.  Its  lower  contact 
is  with  the  Stipa  bunch-grass  prairie  along  the  coast  and  in  the  interior  savannah,  and 
with  Larrea  scrub  at  the  desert's  edge.  Above  it  lies  the  Adenostoma-Ceanothus  chapar- 
ral, with  Adenostoma  and  Artemisia  in  particular  minghng  over  a  narrow  ecotone. 

The  chief  associates  of  the  coast  sagebrush  are  Salvia  mellifera,  S.  apiana,  S.  nivea, 
Eriogonum  fasciculatum,  Rhus  integrifolia,  Eriodictyum  tomentosum,  and  Lotu^  glaber. 


56  GENUS   AHTEMISIA. 

Where  it  forms  low  savannah  it  mixes  with  Stipa  eminens  and  S.  setigera  especially,  or 
with  the  annuals,  such  as  Avena  fatua,  Bromus  maximus,  etc.,  that  have  replaced  the 
native  bunch-grasses.  In  its  relation  to  water,  it  stands  just  below  Adenosloma  and  just 
above  its  climax  associates.  It  is  essentially  a  xerophyte,  ranging  from  a  rainfall  of  25 
to  10  inches.  As  an  indicator,  it  denotes  a  climate  slightly  moister  than  that  of  the 
bunch-grass  prairie  and  drier  than  that  of  the  chaparral.  In  the  chaparral  climax  it 
indicates  disturbance  of  the  soil,  usually  associated  with  alluvial  or  colluvial  deposits. 

USES. 
The  Spanish-Californians  and  other  early  settlers  made  some  use  of  this  plant  for 
medicinal  purposes,  employing  it  for  almost  every  ill.  According  to  Torrey  (Bot.  Mex. 
Bound.  17,  1859),  it  was  used  by  the  Mexican  immigrants  as  a  popular  remedy  against 
cholera,  under  the  name  of  "estafiat."  The  Americans  usually  call  it  "old  man."  The 
foliage  is  not  regularly  browsed  by  cattle,  because  of  the  strong  odor  and  bitter  taste, 
and  although  browsed  by  sheep  and  goats,  this  is  done  only  in  the  absence  of  more 
palatable  food.  As  a  result  the  hillsides  of  western  California  are  in  many  places  covered 
with  a  dense  stand  of  this  brush  where  more  desirable  species  are  destroyed  by  sheep, 
goats,  and  donkeys.  Because  of  its  abundance  and  lightness  the  pollen  is  a  frequent 
cause  of  hay-fever,  as  has  been  determined  by  skin-reaction  tests.  This  has  led  to 
the  use  of  an  extract  prepared  from  the  pollen  as  a  desensitizing  agent  for  the  relief  of 
certain  types  of  hay-fever  on  the  Pacific  Coast.  Beneficial  results  are  secured  only  in 
those  cases  where  positive  reactions  are  first  obtained  with  the  pollen  extract. 

4.  ARTEMISIA  MACROBOTRYS  Ledebour,  Fl.  Alt.  4  :73,  1833.     Plate  4. 

A  perennial  herb  with  a  rootstock,  2  to  4  dm.  high,  probably  nearly  inodorous;  stems 
several  from  a  slender  crown,  simple  below,  erect,  glabrous  or  sparingly  pilose,  plainly 
striate,  yellowish-green;  basal  and  lower  leaves  crowded,  petioled,  4  to  8  cm.  long  including 
petiole,  pinnately  divided  into  several  pairs  of  segments  which  spread  nearly  at  right 
angles,  these  parted  into  lanceolate  very  acute  lobes  which  are  sometimes  again  cleft, 
copiously  long-pilose  or  glabrate;  upper  leaves  similar;  inflorescence  an  elongated  ter- 
minal raceme  or  this  somewhat  branched  and  subpaniculate,  10  to  20  cm.  long,  1  to  3  cm. 
broad;  heads  heterogamous,  peduncled  (peduncles  1  to  5  mm.  long),  mostly  nodding; 
involucre  hemispheric,  3  to  4  mm.  high,  6  to  7  mm.  broad  (much  smaller  at  least  in  some 
Siberian  forms),  bracts  14  to  18,  elliptic  or  the  outer  ovate,  obtuse,  brown  and  scarious 
on  the  margins,  sparingly  villous;  ray-flowers  about  9  to  12,  fertile,  corolla  tapering 
upwards,  about  2  mm.  long;  disk-flowers  about  30  to  50,  fertile,  corolla  funnelform, 
2  to  3  mm.  long  or  only  1.5  in  small-headed  Siberian  forms,  mostly  glabrous;  style- 
branches  of  ray-flowers  acute  to  emarginate,  of  disk-flowers  truncate  and  erose  at  summit; 
achenes  elliptic-turbinate,  4-  or  5-ribbed,  glabrous. 

Western  Yukon  to  Siberia.  Credited  to  Alaska  by  Rydberg  (N.  Am.  Fl.  34:264, 
1916),  but  apparently  rare  there;  widely  distributed  in  Siberia.  Type  locality,  dry 
plains  of  the  Kerlyk  River,  Siberia.  Collections :  The  only  specimen  seen  from  America 
is  one  from  above  Fort  Selkirk,  Yukon  Territory,  July  14,  1899,  Tarleton  111  (NY). 

MINOR  VARIATIONS  AND  SYNONYMS. 

This  plant  is  so  little  known  in  America  that  nothing  can  be  said  as  to  its  possible  variations.  The  extent 
of  variation  in  Siberian  forms  is  mentioned  under  the  heading  of  Relationships. 

1.  Artemisia  laciniata  0  Willdenow,  Sp.  PI.  3: 1843,  1804. — The  original  name  under  which  A.  macrobotrys 
was  described.     Cited  by  Ledebour  as  a  synonym  of  his  A.  macrobotrys. 

2.  Artemisia  tanacetifolia  Linnaeus,  Sp.  PI.  848,  1753. — A  synonym  as  far  as  the  reference  to  Siberia 
is  concerned.  At  least  some  portions  of  the  description,  such  as  "foliis  bipinnatis  subtus  tomentosis  nitidis," 
refer  to  some  other  plant,  probably  A.  nana  Gaudin.  Therefore  the  name  A.  lanacetijolia  can  not  be  taken  up 
for  the  present  species,  notwithstanding  its  early  date  of  publication. 


A.    MACROBOTRYS.  57 

RELATIONSHIPS. 

The  relation  of  A.  macrobotrys  to  A.  parryi,  its  nearest  ally,  has  been  discussed  under 
the  latter,  since  it  is  the  derived  form.  The  only  other  American  species  with  which  it 
is  connected  is  A.  norvegica,  but  the  connection  is  not  very  close.  The  most  striking 
difference  between  the  two  is  in  the  foliage.  In  macrobotrys  the  primary  divisions  of  the 
leaves  spread  nearly  at  right-angles  to  the  rachis,  while  in  norvegica  they  point  forward, 
and  the  shape  of  these  divisions  is  different,  as  shown  in  the  illustrations.  The  heads, 
and  especially  the  disk-corollas,  of  the  former  are  much  smaller  than  in  any  variety  of 
norvegica,  except  a  few  which  are  otherwise  very  different. 

A  much  closer  ally  is  found  in  A.  laciniata  Willdenow  (Sp.  PI.  3:1843,  1804),  a  species 
of  similar  distribution  in  Siberia,  but  not  known  in  America.  There  is  a  striking  similar- 
ity in  habit  and  foliage  and  especially  in  the  strongly  divergent  primary  divisions  of  the 
leaves.  Ledebour  (Fl.  Rossica,  2:582,  1844-46)  states  that  in  laciniata  these  segments 
are  all  reflexed-divaricate,  and  uses  this  as  one  of  his  distinguishing  features.  It  may  be 
expected,  however,  that  more  copious  material  will  show  all  degrees  of  divergence.  It  is 
even  possible  that  macrobotrys  will  eventually  again  become  a  variety  of  laciniata,  as 
Willdenow  once  treated  it  (Sp.  PI.  3:  1843,  1804,  as  A.  laciniata  /3),  but  the  evidence 
at  hand  does  not  justify  this.  The  distinguishing  characters,  as  far  as  indicated  by 
available  collections,  may  be  set  forth  as  follows : 

Artemisia  laciniata  Willdenow.  Artemisia  macrobotrys  Ledebour. 

Primary  divisions  of  the  leaves  mostly  refle.\ed  divari-  Primary  divisions  of  the  leaves  widely  divaricate  but 

cate.  never  reflexed. 

Petiole  wide  and  plainly  canaliculate.  Petiole  slender  and  obscurely  if  at  all  canaliculate. 

Involucre  3  mm.  high,  4  mm.  broad.  Involucre  3  to  4  mm.  high,  6  to  7  mm.  broad. 

Disk-flowers  25  to  30.  Disk -flowers  30  to  50. 

Disk-corollas  1.5  to  2  mm.  long.  Disk-corollas  2  to  3  mm.  long. 

While  additional  collections  will  certainly  necessitate  modifications  of  the  above 
diagnoses,  it  is  hoped  that  the  differences  here  tabulated  will  serve  to  distinguish  these 
two  closely  related  species.  Both  of  them  exhibit  much  variation  in  minor  characters. 
Thus,  in  writing  of  macrobotrys  as  it  occurs  in  Siberia,  Ledebour  (1.  c.)  says: 

"  Variat  foliis  glabriusculis  et  plus  minus  pilosis;  laciniis  latioribus  et  angustioribus,  longioribus  et  brevioribua 
remotioribus  et  approximatis;  rachi  plus  minus  late  alata  et  dentata;  coroUis  pilosiusculis  et  nudis." 

Similar  variations  may  be  expected  among  American  plants,  but  since  the  area  of 
distribution  is  here  much  smaller  than  in  Asia,  it  is  probable  these  are  not  so  marked. 
Detailed  descriptions  of  macrobotrys  are  given  by  Ledebour  in  connection  with  the  original 
description  and  the  species  is  figured  by  him  (Ic.  Fl.  Ross.,  pi.  467). 

From  the  above  considerations  it  seems  fairly  certain  that  macrobotrys,  laciniata, 
and  parryi  form  a  close  natural  group,  and  that  norvegica  is  a  related  species  less  closely 
connected.  Of  these,  macrobotrys  is  perhaps  the  most  primitive.  The  characters  of 
laciniata,  especially  the  extreme  development  of  the  tendency  toward  reflexed  leaf- 
divisions  and  the  reductions  in  heads  and  flowers,  indicate  this  as  a  derived  species. 
Similarly,  parryi  may  be  regarded  as  a  derivative  from  macrobotrys  with  reduced  heads 
and  flowers.  Its  geographic  position  at  outlying  stations  would  support  this  view,  but 
the  tendency  of  its  leaf-segments  to  point  forward  in  some  specimens  indicates  that  it  may 
have  separated  from  the  parent  stock  before  the  character  of  divergence  had  become 
thoroughly  fixed. 

ECOLOGY  AND  USES. 

Nothing  is  known  of  the  ecology  or  uses  of  this  species. 

5.  ARTEMISIA  NORVEGICA  Fries.  Novit.  Fl.  Suec.  ed.  1 :  56, 1817.    Plate  3. 
Boreal  Sagewort. 

A  perennial  herb  with  a  cespitose  caudex  or  short  rootstock,  1  to  5  dm.  high  or  much 
reduced  in  Arctic  forms,  mildly  fragrant;  stems  densely  clustered,  simple  up  to  the 


58  GENUS   ARTEMISIA. 

inflorescence,  erect,  striate,  densely  villous  to  glabrous,  often  reddish  tinged;  basal  leaves 
crowded,  petioled,  1  to  15  cm.  long  including  the  petiole,  1  to  3  times  pinnately  divided 
or  parted  into  lanceolate  or  rarely  linear  or  spatulate  lobes,  varying  from  silvery-silky 
to  glabrous;  upper  leaves  less  dissected;  inflorescence  normally  an  elongated  terminal 
panicle,  10  to  40  cm.  long  and  1  to  5  cm.  broad  but  in  some  forms  much  reduced  and 
raceme-like,  spike-like,  or  head-like;  heads  heterogamous,  peduncled  or  sessile,  commonly 
nodding;  involucre  hemispheric,  4  to  6  mm.  high,  4  to  7  mm.  broad  (up  to  8  mm.  broad 
in  the  original  European  form) ;  bracts  9  to  20,  broadly  elliptic,  obtuse,  with  greenish 
medial  portion  and  broad  brown-scarious  margins,  villous  to  glabrous;  ray-flowers  6 
to  20,  corolla  narrowed  upwards,  2  to  2.5  mm.  long,  obliquely  toothed,  villous  or  glabrous; 
disk-flowers  about  15  to  73,  or  even  up  to  120  in  the  typical  form  and  in  subspecies 
globularia,  fertile,  corolla  funnelform,  2.5  to  3.5  mm.  long,  5-toothed,  villous  to  glabrous 
or  granular;  style-branches  truncate,  those  of  the  disk-flowers  commonly  dilated  and  erose 
at  summit;  achenes  nearly  cylindric  but  with  mostly  raised  ribs,  truncate  or  with  a 
slight  rim  at  summit,  glabrous  but  usually  granuliferous. 

Widely  distributed  in  northern  and  mountainous  regions,  Arctic  shores  of  North 
America  (at  least  as  far  east  as  Camden  Bay)  to  the  Rocky  and  Sierra  Nevada  Mountains, 
northwest  to  Bering  Sea  and  Siberia;  also  in  Scandinavia. 

SUBSPECIES. 

There  is  a  very  considerable  range  of  variation  in  the  size  of  the  plant,  the  branching 
of  the  inflorescence,  and  the  amount  of  pubescence.  The  number  of  recognizable 
variations  is  not  so  great,  however,  as  the  long  Ust  of  described  segregates  would  seem 
to  indicate.  This  is  because  the  latter  have  been  too  often  based  upon  pubescence  and 
other  characters  which  are  strongly  fluctuating,  even  over  small  geographic  areas. 
The  more  striking  variations  in  North  America  are  the  following: 

Key  lo  the  Subspecies  of  Artemisia  norvegiea. 
Heads  in  elongated  spikes,  racemes,  or  panicles. 

Inflorescence  open-paniculate  or  loosely  racemose;  plants  mostly  2  to  5  dm.  high;  pubes- 
cence villous  or  wanting. 
Leaf-blades  mostly  less  than  4  cm.  long,  short-oblong  or  roundish  in  outline;  invo- 
lucre 5  to  6  mm.  high.     (Not  American;  included  for  comparison  only.)' Typical  A.  norvegiea. 

Leaf-blades  mostly  over  4  cm.  long,  elongated-oblong  in  outline;  involucre  4  to  5.2 

mm.  high .•  •  •    (a)  saxatilia  (p.  58). 

Inflorescence  a  narrow  raceme  or  somewhat  spike-like;  plants  mostly  2, dm.  or  less  high; 

pubescence  usually  canescent  or  appressed  silverv-silky .••••■■. (^)  heteropkylla  (p.  59). 

Heads  in  a  dense  globoid  terminal  cluster.     Northern  dwarf  forms  sometimes  simulated 
by  reduced  plants  of  heterophylla. 
Lower  leaf-blades  simply  or  only  2  times  divided;  petiole  broad,  involucre  more  than 

5  mm.  broad (c)  globularia  (p.  59). 

Lower  leaf-blades  2  or  3  times  divided;  petiole  narrow,  involucre  mostly  less  than  5  mm. 

broad (d)  glomerata  (p.  60). 

5a.  Artemisia  norvegica  saxatilis  (Besser). — Stems  1.5  to  5  dm.  high;  foliage 
varying  from  merely  somewhat  pilose  (as  in  the  original  A.  norvegica)  to  copiously  villous 
{A.  saxicola  Rydberg,  minor  variation  9)  or,  on  the  other  hand,  to  perfectly  glabrous 
{A.  levigata  Standi ey,  minor  variation  5);  lower  leaves  5  to  15  cm.  long,  the  blade 
usually  elongated-elliptic  or  oblong  in  outline  and  2  to  8  cm.  long  (usually  over  4  cm. 
long),  much  divided  into  linear-lanceolate  acute  lobes;  inflorescence  openly  paniculate, 
10  to  30  cm.  long,  sometimes  narrow  and  racemose,  especially  in  Alaskan  forms ;  heads 
large,  the  involucre  4  to  5.2  mm.  high;  disk-flowers  33  to  75,  their  corollas  2.5  to  3.5 
ram.  long.  (A.  chamissoniana  saxatilis  Besser;  Hooker,  Fl.  Bor.  Am.  1:324,  1833). 
Alberta  (and  probably  farther  to  the  northeast),  to  the  high  mountains  of  southern 
Colorado,  the  Sierra  Nevada  of  California,  and  north  through  Washington  and  Alaska 

'  Typical  A.  norvegica  ghuuld  perhaps  be  admitted  to  the  North  American  flora.  Wille  records  the  species  from  Green- 
land (Engler's  Bot.  Jahrb.  36,  beiblatt  81:68,  1905).  but  he  did  not  distinguish  between  the  typical  and  the  American  sub- 
species. 


A.    NORVEGICA.  59 

to  eastern  Siberia.  Type  locality,  Rocky  Mountains.  Collections:  Union  Peak, 
Wyoming,  Nelson  897  (Gr);  high  mountains  about  Empire,  Colorado,  Patterson  218 
(Gr);  Ethel  Peak,  Larimer  County,  Colorado,  Goodding  1891  (Gr,  NY,  UC,  US);  near 
Mineral  King,  southern  Sierra  Nevada  Mountains,  California,  Hall  and  Bdbcock  5659 
(DS,  UC);  mountains  above  Bear  Valley,  near  Lake  Tahoe,  California,  July  29,  1889, 
Sonne  (UC) ;  Horse  Shoe  Basin,  Okanogan  County,  Washington,  Elmer  705  (NY,  nearly 
glabrous,  minor  variation  1,  A.  arctica  Lessing);  Olympic  Mountains,  Washington, 
Elmer  2618  (DS,  NY,  moderately  pubescent,  intermediate  to  minor  variation  1,  ^. 
arctica  Lessing);  head  of  Smoky  River,  Alberta,  Riley  30  (US,  glabrous  form,  tjT^e  of 
A.  levigata  Standley,  minor  variation  9);  Fisk  Creek,  Selkirk  Mountains,  British  Colum- 
bia, Butters  and  Holway  436a  (Gr,  minor  variation  \,  A.  arctica  Lessing);  Glacier  River, 
Unalaska,  Van  Dyke  73  (Gr,  minor  variation  1,  A.  arctica  Lessing,  green  and  nearly 
glabrous);  St.  Paul  Island,  Bering  Sea,  Macoun  94013,  very  pubescent  (NY),  and  94OI4, 
green  and  nearly  glabrous  (Gr). 

56.  Artemisia  norvegica  heterophylla  (Besser). — Stems  0.5  to  2  dm.  high;  foliage 
silvery-canescent  or  silky,  usually  densely  so  (least  so  or  even  glabrate  in  A.  comata 
Rydberg,  minor  variation  2),  somewhat  villous  with  spreading  hairs  (in  A.  richardsoniana 
Besser,  minor  variation  12) ;  lower  leaves  1  to  6  cm.  long,  the  blade  roundish  in  outline 
and  1  to  3  cm.  long,  1  to  3  times  dissected  into  linear  barely  acute  divisions;  inflorescence 
spike-like,  4  to  10  cm.  long,  congested  toward  the  summit  but  often  open  and  raceme-like 
below;  heads  small,  the  involucre  3.5  to  4.5  mm.  high;  disk-flowers  10  to  25  or  more, 
their  corollas  3  to  3.5  mm.  long.  {A.  heterophylla  Besser,  Nouv.  Mem.  Soc.  Nat.  Mosc. 
3:74,  1834.)  Eastern  Siberia  and  Arctic  shores  of  North  America  to  Great  Slave  Lake 
and  the  high  mountains  of  Washington.  Type  locality,  St.  Lawrence  Bay,  Bering  Strait, 
eastern  Siberia.  Collections:  Arctic  Coast  of  Canada,  Richardson  (US,  type  collection 
of  A.  richardsoniana  Besser,  minor  variation  12) ;  Camden  Bay,  Alaska,  on  gravel  tundra, 
Johansen  122  (NY,  type  collection  of  A.  comata  Rydberg,  minor  variation  3);  sandspit 
at  Martin  Point,  Alaska,  Johansen  134  (NY,  minor  variation  3,  A.  comata  Rydberg); 
Bernard  Harbor,  northern  Canada,  in  gravel  tundra,  Johansen  337  (NY,  form  with 
villous  pubescence,  A.  richardsoniana  Besser,  minor  variation  12);  Bernard  Harbor, 
northern  Canada,  on  sandy  slopes  and  sand  dunes,  Johansen  304  o^nd  304a  (NY,  form 
with  silvery  pubescence  and  dark-margined  bracts,  minor  variation  8,  A.  hyperborea 
Rydberg,  of  which  Johansen's  304  is  the  type  number);  Copper  Island,  September  3, 
1891,  Macoun  (Gr,  form  near  minor  variation  8,  A.  hyperborea  Rydberg);  vicinity  of 
Norton  Sound,   Alaska,    1900,   Macgregor;  Mount  Rainier,   Washington,   August  27, 

1896,  Flett  (US,  type  of  A.  tacomensis  Rydberg,  minor  variation  14). 

5c.  Artemisia  norvegica  globularia  (Chamisso). — Stems  0.4  to  1  dm.  high; 
foliage  gray  with  a  dense  silky-villous  pubescence,  varying  to  sparsely  pubescent  and 
green;  lower  leaves  1  to  3  cm.  long,  the  blade  flabelliform  or  obovate  in  outline  and  less 
than  1  cm.  long,  once  or  twice  ternately  divided  into  broadly  linear  or  elliptic  acute 
divisions,  the  petiole  wide  and  flat;  inflorescence  a  single  terminal  globoid  cluster  of 
heads,  1  to  2  cm.  across;  heads  rather  large,  the  involucre  4  to  6  mm.  high;  disk-flowers 
about  50  to  120,  their  corollas  3  to  4  mm.  long.  {A.  globularia  Chamisso;  Besser,  Nouv. 
Mem.  Soc.  Nat.  Mosc.  3:64,  1834.)  Western  Alaska  and  eastern  Siberia.  Type 
locality,  St.  Lawrence  Bay,  Siberia.  Collections:  St.  George  Island,  Bering  Sea,  July 
31,  1891,  Macoun  (Gr);  St.  George  Island,  Bering  Sea,  June  29,  1920,  Johnston  (SF, 
densely  pubescent,  gray);  same,  but  on  cliffs,  August  13,  1920,  Johnston  (SF,  sparsely 
pubescent,  green);  St.  Paul  Island,  Bering  Sea,  August,  1920,  Hanna  (SF);  St.  Paul 
Island,  Bering  Sea,  Macoun  94015  (Gr,  NY);  St.  Paul  Island,  Bering  Sea,  August  15, 

1897,  Kincaid  (UC);  St.  Matthew  Island,  Bering  Sea,  Macoun  87  (NY);  type  collection 
(Gr,  ex-herb.  Acad.  Petrop.). 


60 


GENUS   AKTEMISIA. 


5d.  Artemisia  norvegica  glomerata  (Ledebour). — Stems  0.4  to  1.2  dm.  high; 
foliage  gray  with  a  dense  silky-villous  pubescence;  lower  leaves  0.8  to  2  cm.  long,  the 
blade  flabelliform  or  orbicular  in  outline  and  less  than  1  cm.  long,  2  or  3  times  ternately 
divided  into  linear  acute  divisions,  the  petiole  slender;  inflorescence  a  single  dense  terminal 
globoid  cluster  of  heads,  1  to  2  cm.  across;  heads  small,  the  involucre  3.5  to  5  mm.  high; 
disk-flowers  16  or  more,  their  corollas  about  2.5  mm.  long.  (A.  glomerata  Ledebour, 
Mem.  Acad.  St.  Petersb.  5:564,  1815.)  Western  Alaska  to  eastern  Siberia  and  the 
Kurile  Islands.  Type  locality,  St.  Lawrence  Bay,  Siberia.  Collections:  Cape  Thompson, 
Alaska,  Muir  80  (Gr);  Arakamtchetchene  Island,  Bering  Straits,  1853-56,  Wright  (Gr); 
St.  Lawrence  Bay,  eastern  Siberia,  July  24,  1895,  Sharp  (Phila.);  St.  Lawrence  Bay, 
Eschscholtz  (Gr,  ex-herb.  Ledebour). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  A.  ARCTICA  Lessing,  Linnaea  6:213,  1831. — The  nearly  glabrous  form  of  A.  norvegica  saxatilis.  Most 
common  in  the  far  Northwest,  but  specimens  which  are  almost  entirely  glabrous  come  from  as  far  south  as 
the  southern  Sierra  Nevada  of  California  (Purpus  1635,  UC),  and  all  degrees  of  pubescence  are  found  in  dif- 
ferent collections.  It  seems  quite  unlikely  that  the  amount  of  pubescence  is  other  than  a  response  to  ecologic 
conditions.  It  is  therefore  not  surprising  to  find  that  in  the  far  Northwest  the  plants  are  mostly,  although 
not  all,  of  the  nearly  glabrous  type,  and  that  in  the  arid  Rocky  Mountain  districts  they  are  strongly  pubescent, 
while  in  the  Cascades  and  Sierra  Nevada  occur  both  sorts  with  numerous  intermediate  forms.  A.  arctica 
also  differs,  according  to  Rydberg,  in  the  inner  bracts,  which  are  said  to  be  "ovate,  obtuse,  or  rarely  acutish, 
with  a  broadly  lanceolate  green  center,"  while  those  of  true  saxatilis  {A.  saxicola  Rydberg)  are  said  to  be 
"ovate,  acute,  with  a  narrowly  lanceolate  green  center."  There  is,  to  be  sure,  some  variation  in  the  bracts, 
but  these  run  parallel  neither  with  the  variations  in  pubescence  nor  with  geographic  distribution,  as  is  shown 
by  the  series  of  12  bracts  represented  in  figure  5.  Various  forms  referred  to  A.  arctica  by  Besser,  Gray,  and 
others  belong  partly  to  subspecies  saxatilis  and  partly  to  subspecies  heterophylla.     The  type  locality  of  arctica 


-Inner  bracts  of  Artemisia  norvegica  saxatilis:  a  to  /,  inner  bracts  from  plants  referable  to  true  saxatilis  because  of 
the  strong  pubescence  on  stems  and  foliage;  a  to  I.  inner  bracts  from  plants  referable  to  minor  variation  1 
(.4.  arctica  Lessing)  because  of  the  nearly  glabrous  stems  and  foliage,  a,  from  Colorado  (69460  UC);  b,  from 
Colorado  (489332  US);  c.  from  Colorado  (29773  UC);  d,  from  California  (91243  UC);  e.  from  California  (193585 
UC);  /,  from  California  (63517  UC);  g,  from  Alaska  (204365  UC);  h,  from  Alaska  (204501  UC);  i.  from  Alaska 
(91242  UC);;,  from  California  (29703  UC);  t,  from  California  (40555  UC);J,from  California  (91240  UC).  All  X  6. 


2.  A.  CHAMissoNiANA  SAXATILIS  Besser,  in  Hooker  Fl.  Bor.  Am.  1:324,  1833. — .4.  norvegica  saxatilis. 
^3.  A.  COMATA  Rydberg,  N.  Am.  Fl.  34:263,  1916. — A  form  combining  the  greenish  herbage  and  elongated 
leaf-blades  of  A.  norvegica  saxatilis  with  the  reduced  stature  (1.  to  1.5  dm.)  and  narrow,  racemo.se  inflorescence 
of  heterophylla.  Although  the  stems  and  foliage  are  nearly  glabrous,  the  rachis  of  the  inflorescence  and  the 
peduncles  are  notably  white-villous.  The  involucre  is  very  dark  and  nearly  glabrous.  Type  locality,  Collinson 
Point,  Camden  Bay,  Alaska.  (Illustration  in  Macoun  and  Holm,  Rep.  Canadian  Arctic  Exped.  5:  plate  13. 
figs.  3  and  6.) 


A.    NORVEGICA.  61 

4.  A.  cooLEYAE  Rydberg,  1.  c.  265. — Placed  next  to  A.  parryi  in  the  North  American  Flora  because  of  its 
small  heads,  glabrous  herbage,  and  "light  brown"  margins  to  the  involucral  bracts.  The  inflorescence,  too, 
has  the  long,  ascending  branches  of  parryi,  but  this,  as  also  the  small  size  of  the  heads,  may  be  the  result  of 
a  deformity.  On  the  whole,  the  plant  seems  more  like  an  aberrant  specimen  of  A.  norvegica  saxaiilis.  The 
leaves  with  slender,  attenuate,  forward-pointing  lobes  are  almost  identical  with  those  of  some  forms  of  saxatilis; 
for  example,  Howell's  plant  from  Yes  Bay,  Alaska  (August  21,  1895,  NY)  or  Elmer's  plant  from  Washington 
(Elmer  705,  NY).  The  glabrous  character  also  occurs  in  saxatilis  of  the  levigata  form.  The  distinction 
between  light  brown  and  fuscous,  as  applied  to  the  color  of  bract-margins,  is  too  subtle  for  use  as  a  distinguishing 
character.  The  final  disposal  of  A.  cooleyae  may  await  the  assembling  of  copious  material  in  perfect  condition. 
Type  locaUty,  above  Silver  Bow  Basin,  Juneau,  Alaska. 

5.  A.  GLOBULARiA  Chamisso,  Besser,  Nouv.  Mem.  Soc.  Nat.  Mosc.  3:64,  1834. — A.  norvegica  glohularia. 

6.  A.  GLOMERATA  Ledebour,  Mem.  Acad.  St.  Petersb.  5:564,  1815. — A.  norvegica  glomerata. 

7.  A.  HETEROPHYLLA  Besser,  1.  c,  74,  1834. — A.  norvegica  heterophylla. 

8.  A.  HYPERBOREA  Rydbcrg  1.  c,  262. — A.  norvegica  helerophylla.  The  pubescence  in  the  type  specimen 
is  dense,  closely  appressed,  and  silvery,  even  in  the  inflorescence,  and  the  bracts  are  conspicuously  dark- 
margined.  Type  locality,  sand  dunes  at  Bernard  Harbor,  Northwest  Territory.  (Illustrated  in  Macoun 
and  Holm,  Rep.  Can.  Arctic  Exped.  5:  Plate  13,  figs.  2  and  4.) 

9.  A.  LEVIGATA  Standley,  Smiths.  Misc.  Coll.  56":  2,  1912. — The  perfectly  glabrous  form  of  A.  norvegica 
saxatilis.  As  already  indicated  under  A.  arctica,  of  this  list,  the  amount  of  pubescence  is  exceedingly  variable 
and  can  not  be  correlated  with  other  characters.  The  type  of  levigata  came  from  the  Smoky  River,  Alberta, 
and  absolutely  glabrous  plants  are  known  also  from  the  middle  Sierra  Nevada  of  California  {Brewer  2129,  UC). 
The  original  specimen  of  A.  arctica  is  a  comparatively  low  plant  (3  dm.?)  with  a  racemose  inflorescence,  but 
paniculate  forms  also  are  sometimes  essentially  glabrous  {Walker  932,  from  Alaska)  while  the  racemose  forms 
are  commonly  pubescent  {Walker  770  and  Funston  93,  both  from  western  Alaska).  It  is  thus  evident  that 
the  use  of  such  criteria  would  necessitate  the  acceptance  of  several  more  species  than  have  as  yet  been  proposed. 

10.  A.  MiNUTA  Rydberg,  1.  c,  261. — Provisionally  placed  by  its  author  between  forms  here  referred  to 
A.  norvegica  heterophylla;  also  keyed  with  A.  pedatifida  because  of  the  somewhat  woody  stems.  "Flowers 
unknown  and  therefore  its  place  in  the  genus  uncertain."  The  type  specimen,  which  came  from  Medicine 
Hat,  Alberta,  is  not  identifiable. 

11.  A.  NORVEGICA  PACIFICA  Gray,  Syn.  FI.  N.  Am.  P:371,  1884. — A.  norvegica  saxatilis.  The  relation  of 
this  form  to  the  original  saxatilis  is  discussed  under  A.  arctica,  of  which  variety  pacifica  is  an  exact  synonym. 

12.  A.  RiCHARDsoNiANA  Besser,  Bull.  Soc.  Nat.  Mosc.  9 :  64,  1836. — Here  referred  to  A.  norvegica  heterophylla, 
although  further  collections  and  field  study  may  furnish  characters  entitling  it  to  separate  rank.  The  only 
distinguishing  feature  thus  far  assigned  to  it  is  the  variable  one  of  its  more  spreading  villous  pubescence. 
Type  locality,  Arctic  Coast  of  Canada.  (Illustrated  by  Macoun  and  Holm,  Rep.  Can.  Arctic  Exped.  5: 
plate  13,  figs.  1  and  5,  1921.) 

13.  A.  sAxicOLA  Rydberg,  Bull.  Torr.  Club  32:128,  1905. — A.  norvegica  saxatilis.  In  raising  the  original 
A.  chamissoniana  saxaiilis  Besser  to  specific  rank,  Rydberg  changed  the  name  to  saxicola  because  of  the  earlier 
A.  saxatilis  Waldstein  and  Kitaibel,  1804.  This  last  is  generally  regarded  as  a  synonym  of  A.  camphorala 
Villar,  a  European  species. 

14.  A  TACOMENsis  Rydberg,  N.  Am.  Fl.  34:262,  1916. — .4.  norvegica  heterophylla.  According  to  Rydberg, 
the  stems  are  less  than  1  dm.  high,  the  basal  leaves  1  to  1.5  cm.  long,  the  herbage  silvery-canescent,  and  the 
involucre  densely  white-villous,  whereas  in  the  original  heterophjUa  the  stems  are  1  to  2  dm.  high,  the  basal 
leaves  3  to  6  cm.  long,  the  herbage  silky-villous,  and  the  involucre  densely  villous.  The  type  of  tacomensis, 
which  came  from  Mount  Rainier,  Washington,  substantiates  these  distinctions,  but  other  specimens  from  Mount 
Rainier  (August  20,  1889,  Greene,  UC)  which  must  be  taken  as  expressions  of  the  same  form,  have  stems  1.2 
to  1.6  dm.  high,  basal  leaves  1.5  to  5  cm.  long,  and  involucres  densely  lanate  as  originally  described  for  hetero- 
phylla. In  view  of  these  facts,  .4.  tacomensis  can  not  be  accepted  as  more  than  a  form  of  heterophylla  with 
unusually  smooth  and  silvery  fohage.  The  involucral  bracts  of  these  southern  plants  are  quite  pale  along  the 
margins  as  contrasted  with  the  usually  dark-margined  bracts  in  forms  from  the  far  north. 

15.  A.  TYERELLi  Rydberg,  1.  c,  262. — A  rare  plant  known  only  from  an  incomplete  specimen  gathered  in 
northern  British  Columbia.  Probably  best  referred  to  A.  norvegica  heterophylla  but  robust,  the  stems  2  to  3 
dm.  high.    The  herbage  is  silky-canescent  or  silvery. 

RELATIONSHIPS. 

Artemisia  norvegica  is  not  of  American  origin.  This  is  clear  from  a  consideration  of  the 
fact  that  all  of  the  species  on  this  continent  to  which  it  is  most  closely  related  possess 
certain  specialized  features  wanting  in  norvegica.  This  indicates  either  that  they  are 
themselves  derivatives  of  norvegica,  or  have  come  down  from  some  more  ancient  ancestral 
stock.     The  species  here  referred  to  are  A.  senjavinensis,  A.  macrobotrys,  and  A.  parryi. 


62  GENUS   ARTEMISIA. 

The  relationship  of  each  of  these  to  norvegica  will  be  discussed  under  the  respective 
species.  The  exact  place  of  origin  of  norvegica  probably  will  never  be  determined,  but 
from  the  facts  of  distribution  it  seems  to  have  been  somewhere  near  the  central  portion 
of  Eurasia.  After  its  migration  toward  the  north,  the  species  spread  west  and  east 
along  the  Arctic  shores  and  seems  to  have  broken  up  into  two  principal  stocks,  one 
resulting  in  the  form  represented  by  the  present  nomenclatorial  type,  the  other  yielding 
a  group  of  forms  centering  around  subspecies  saxatilis.  The  former  is  of  northwestern 
distribution,  being  most  abundant  in  Scandinavia;  the  latter  belongs  to  extreme  north- 
eastern Asia  and  America.  No  specimens  are  at  hand  from  the  intervening  area,  that 
is,  northern  Siberia,  and  it  seems  from  the  literature  that  no  forms  of  the  species  are 


Inflorescence  open.  Inflorescence  close, 

paniculate  or  loosely  narrowly  racennose  fo 

racemose  ;  large  glomerulate ;  low  plants, 

plants,  mostly  green  mostly  canescent  or  silky 


Fio.  6. — Phylogenetic  chart  of  the  subspecies  of  Artemisia  norvegica. 

there  present.  If  further  exploration  proves  this  to  be  the  case,  then  the  close  similarity 
between  Scandinavian  and  American  forms  will  be  most  remarkable.  It  is  quite  possible, 
however,  that  the  species  has  reached  America  through  a  route  extending  westerly 
from  Scandinavia,  since  Wille  reports  it  in  Greenland  (Engler's  Bot.  Jahrb.  36,  beiblatt 
81 :58,  1905).  The  Old  World  and  Rocky  Mountain  types  are  so  nearly  alike  in  most  of 
their  characters  that  W.  J.  Hooker  was  unable  to  see  any  differences  whatever  between 
certain  specimens  from  Norway  and  others  from  the  Rocky  Mountains  (Hooker,  Fl. 
Bor.  Am.  1:325,  1833).  But  a  careful  comparison  of  large  series  from  both  regions 
establishes  certain  decided  tendencies  which  render  their  subspecific  separation  highly 
desirable,  while  at  the  same  time  the  overlapping  in  all  essentials  makes  their  specific 
segregation  impossible.  Typical  norvegica,  as  it  grows  in  Scandinavia,  is  a  plant  with 
leaf-blades  often  as  broad  as  long  through  the  congestion  of  the  segments  near  the  end 
of  the  rachis;  the  heads  average  larger  than  in  any  American  variety  (see  table  4),  and 
the  peduncles  are  usually  longer.  In  all  of  these  characters,  however,  it  is  sometimes 
matched  by  forms  of  subspecies  saxatilis.  Although  the  two  are  widely  separated 
geographically,  there  are  some  specimens  of  each  that  can  not  be  positively  identified 


A.    NORVEGICA,  63 

on  morphological  characters  alone.  The  degree  of  difference  in  the  size  of  the  head  and 
the  amount  of  overlapping  is  indicated  in  table  4,  where  these  features  are  brought  out 
in  the  columns  headed  "Involucre."  The  size  of  the  head  is  also  proportional  to  the 
number  of  flowers.  While  this  number  will  not  serve  to  differentiate  the  two  forms, 
because  of  the  amount  of  variation,  a  decided  tendency  towards  the  higher  numbers  is 
seen  in  the  specimens  from  the  Old  World. 

While  the  Scandinavian  plants  exhibit  but  little  variation  among  themselves,  the 
American  branch  yields  a  considerable  number  of  minor  derivatives,  a  majority  of 
which  are  ecologic,  at  least  in  origin.  These  differ  from  one  another  principally  in  habit, 
type  of  inflorescence,  size  of  heads,  and  especially  in  the  amount  of  pubescence.  Some 
have  been  given  specific  names,  and  these  are  here  treated  under  the  heading  "Minor 
variations." 

In  addition  to  the  two  subspecies  already  discussed,  there  are  three  which  are  alike  in 
that  all  have  undergone  a  reduction  in  the  inflorescence.  This  has  been  accompanied 
by  a  dwarfing  in  the  plant  itself  and  the  pubescence  usually  is  not  only  more  copious, 
but  has  taken  on  a  close,  canescent,  often  silky  character.  The  subspecies  are  hetero- 
phylla,  globularia,  and  glomerata.  They  are  restricted  to  northern  North  America  and 
the  extreme  easterly  part  of  Siberia.  This  group  (fig.  6)  is  indicated  as  having  been 
evolved  before  the  segregation  of  saxatilis,  but  there  is  no  evidence  other  than  that 
obtained  from  the  leaves  to  substantiate  this  arrangement.  On  the  basis  of  geographic 
distribution,  it  is  simpler  to  assume  that  the  branch  is  an  offshoot  from  saxatilis,  in 
which  the  leaf-blades  have  retained  the  short,  rounded  outline  sometimes  found  in  that 
subspecies.  The  least  amount  of  modification  has  taken  place  in  subspecies  heterophylla. 
In  this  the  inflorescence  has  been  reduced  from  the  usual  open  panicle  to  a  spike,  and 
when  this  is  much  shortened  it  becomes  almost  capituliform,  as  in  some  of  the  specimens 
of  the  type  collection  of  A.  richardsoniana,  here  referred  to  heterophylla.  The  subspecies 
is  widely  distributed  in  northwestern  America,  which  accounts  for  the  presence  of 
several  intergrading  forms. 

The  final  stage  in  the  reduction  of  the  inflorescence  is  reached  by  globularia  and 
glomerata.  Here  the  heads  are  always  in  dense  terminal  clusters.  In  these  northern 
derivatives  the  foliage,  as  well  as  the  stem  and  inflorescence,  fails  to  reach  full  develop- 
ment and  the  pubescence  is  not  so  white,  appressed,  and  silvery  as  in  heterophylla. 
While  probably  of  ecologic  origin,  either  from  this  or  from  some  similar  subspecies, 
their  best  characters  seem  now  to  be  fixed,  as  indicated  by  the  absence  of  a  completely 
intergrading  series.  Much  more  copious  collections  from  the  far  north  are  needed  before 
such  points  can  be  finally  determined.  The  subspecies  globularia  and  glomerata  are 
closer  in  general  aspect  than  any  other  pair  within  the  species,  but  on  the  basis  of  the 
statistics  presented  in  table  4  they  are  the  most  distinct.  The  total  absence  of  over- 
lapping in  some  of  the  characters  tabulated  might  seem  good  evidence  of  their  specific 
segregation.  However,  it  should  be  pointed  out  that  the  differences  are  all  of  one 
order,  namely,  the  smaller  number  of  flowers  and  their  smaller  size  in  glomerata,  with 
the  inevitable  result  of  a  reduction  in  the  size  of  the  involucre.  This  character,  even 
when  taken  in  connection  with  the  tendency  towards  a  more  simply  cut  foliage,  can 
scarcely  be  of  specific  value,  especially  when  so  few  collections  are  available  for  study. 
Moreover,  heterophylla  is  also  to  be  taken  into  account.  By  injecting  its  measurements 
into  the  series  a  nearly  complete  gradation  is  obtained,  even  from  the  small  number 
of  specimens  tabulated.  The  additional  criterion  of  pubescent  corollas  in  glomerata 
as  contrasted  with  glabrous  or  only  glandular-granuliferous  ones  in  globularia  has  been 
used  by  Besser  (DeCandoUe,  Prodr.  6: 116,  1837)  and  others,  but  the  unreliability  of  this 
character,  which  has  been  demonstrated  in  the  discussion  on  criteria,  is  here  evidenced 
by  the  nearly  entire  absence  of  hairs  on  the  corollas  of  the  three  collections  of  glomerata 


64 


GENUS   ARTEMISIA. 


cited  in  table  4,  as  well  as  of  all  the  globularia  material  available.  Ledebour  (Fl. 
Ross.  2:588,  1844-46)  describes  both  as  having  pilose  corollas.  The  shape  of  the  disk- 
corollas  is  perhaps  of  greater  significance.  There  seems  to  be  a  tendency  in  all  of  these 
dwarf  subspecies  towards  a  sudden  enlargement  of  the  throat,  as  shown  in  plate  3,  this 


Table  4. — Variation  in  the  subspecies  of  Artemisia  norvegica. 


No.  of 
bracts. 


No. 
of  ray- 
flowers. 


No. 
of  disk- 
flowers. 


Typical  A.  norvegica: 

Kongsvold,  Norway. 
Dovre,  Norway .... 

Do 

Ahlberg,  Norway. . . 
Doorenses,  Norway. 

Average 


Gr 

Gr 

Gr 

13388  US 

US 


Subspecies  saxatilis: 

Disenchantment  Bay,  Alaska. 

Nome,  .\laska 

Silver  Bow  Basin,  Alaska. . . . 
White  Pass,  Yukon,  Alaska. . 

Vixen  Inlet,  Alaska 

Kuiu  Island,  Alaska 

Short  Bay,  Alaska 

Upper  Tnickee,  Calif 

Do 

Yosemite  Park,  Calif 

Mineral  King,  Calif 

Farewell  Gap,  Calif 

Little  Kern,  Calif 

Clear  Creek,  Colo 

Ethel  Peak,  Colo 


91242  UC 
91245  UC 
29727  UC 

SF 
204365  UC 
204501  UC 
91241  UC 
193585  UC 
91244  UC 
29704  UC 

91243  UC 
63517  UC 
91240  UC 
29773  UC 
69460  UC 


Average . 


Subspecies  heterophylla: 

Bernard  Harbor,  Can 

Do 

Sarauna,  Bering  Island 

Mount  Rainier,  Washington. 


NY 

NY 

US 

29776  UC 


Subspecies  globularia: 

St.  George  Island,  Bering  Sea 
St.  Matthews  Is.,  Bering  Sea. 

Do 

Do 

Do 

St.  George  Island,  Alaska 

Do 

St.  Paul  Island,  Alaska 


Gr 
Gr 

NY 
Gr 
73910  UC 
SF 
SF 
SF 


Average . 


Subspecies  glomerala: 
St.  Lawrence  Bay. 

Do 

Bering  Strait 


Gr 

Phila 

Gr 


Average . 


36 

73(!) 

73 

34 

46 

64 

66 


'  The  disk-flowers  often  fall  out  of  the  involucres  in  dried  specimens.     For  this  reason  the  lower  numbers  are  not  reliable. 
This  applies  especially  to  the  last  two  subspecies,  of  which  the  material  is  rather  poor. 


A.    SENJAVINENSIS.  65 

being  most  noticeable  in  glomerata.  But  the  meager  material  at  hand  scarcely  justifies 
the  taxonomic  use  of  this  feature  at  present.  The  probable  explanation  as  to  the 
phylogeny  of  the  last  three  subspecies  is  that  each  represents  a  distinct  evolutionary  line 
which  has  become  fixed  through  isolation. 

ECOLOGY  AND  USES. 
Artemisia  norvegica  is  a  perennial  herb  with  caudex  or  short  rootstock,  which  blooms 
from  early  July  to  October.  It  forms  clans  in  alpine  and  Arctic  meadows  and  subalpine 
forests,  and  sometimes  becomes  a  consocies  on  stony  slopes  or  in  burned  areas.  It 
usually  indicates  moist  areas  in  forests,  where  it  is  often  associated  with  Carex,  Juncus, 
Erigeron,  Mimulus,  etc.     No  uses  are  known  for  this  species. 

6.     ARTEMISIA  SENJAVINENSIS  Besser,  Nouv.  Mem.  See.  Mosc.  3:65,  1834. 
Plate  4. 

A  perennial  herb  with  a  thick  multicipital  caudex,  about  0.5  to  1  dm.  high,  the  odor 
not  known;  stems  numerous,  forming  dense  tufts,  simple  above  the  basal  branches,  the 
central  ones  erect,  the  outer  ones  spreading,  densely  villous  with  long  shaggy  white  or 
tawny  hairs;  basal  leaves  densely  crowded,  sessile,  less  than  1.5  cm.  long,  simply  3-  to 
5-cleft  into  ovate,  acute  lobes,  very  densely  silky-villous  like  the  stems,  the  hairs  longer 
than  the  lobes  and  nearly  concealing  the  leaf;  upper  leaves  1  to  2  cm.  long,  cleft  less  than 
halfway  into  elliptic  rather  obtuse  lobes,  similarly  silky-hirsute;  inflorescence  a  congested 
globoid  terminal  spike,  1  to  2  cm.  long  and  of  equal  breadth ;  heads  heterogamous,  sessile, 
erect;  involucre  campanulate,  about  4  mm.  high  and  4  to  5  mm.  broad;  bracts  about  8, 
elliptic,  denticulate,  obtuse,  with  brown  scarious  margins,  densely  long-villous;  ray- 
flowers  5  to  8,  fertile,  corolla  tubular,  about  2  to  2.4  mm.  long,  lobed,  granular;  disk- 
flowers  10  to  20,  fertile,  corolla  funnelform,  about  2.5  to  3  mm.  long,  5-toothed,  granular; 
style-branches  of  ray-flowers  ligulate,  truncate,  entire,  of  disk-flowers  dilated,  rounded 
and  erose  at  summit;  achenes  nearly  cylindric,  with  about  5  vertical  ribs  or  nerves, 
glabrous. 

Western  Alaska  and  eastern  Siberia.  Type  locality,  Senjavin  Sound,  Siberia.  Collec- 
tions: Kotzebue  Sound,  western  Alaska,  " Beechey"  (Gr,  ex-herb.  Hooker);  same  locality, 
"Arnott"  (NY);  Arakamtchetchene  Island,  Bering  Straits,  1853-56,  Wright  (NY,  US). 
Siberian  collections  as  far  as  known  include  only  the  following:  Type  collection,  Mertens 
(Gr,  ex-herb.  Acad.  Petrop.);  Fretum  Senjavin,  Bongard  (NY,  other  species  also  have 
been  distributed  with  these  data) ;  Terra  Tschuktschorum,  St.  Lawrence  Bay,  Eschscholtz 
(according  to  Ledebour,  Fl.  Ross.  2:589,  1844-46). 

SYNONYMS. 

1.  Artemisia  androsacea  Seeman,  Botany  Voy.  Herald  34,  1852. — The  excellent  plate  accompanying 
the  original  description  leaves  no  doubt  that  this  is  exactly  A.  senjavinensis.  Type  locality,  Kotzebue  Sound, 
Alaska. 

2.  A.  SEMAViNENSis  Besscr,  Nouv.  Mem.  Soc.  Mosc.  3:65,  1834.— The  original  spelling  of  the  specific  name; 
corrected  to  senjavinensis  by  Besser  (Bull.  Soc.  Nat.  Mosc.  9:64,  1836). 

RELATIONSHIPS. 

There  is  considerable  evidence  to  support  the  view  that  this  is  a  reduced  far-northern 
derivative  either  of  A.  macrobotrys  or  A.  norvegica.  The  small  size  of  the  heads  might 
seem  to  indicate  the  former,  but  the  very  dense  and  persistent  pubescence  is  more  like 
that  of  certain  forms  of  the  latter,  which  also  includes  a  small-headed  subspecies  glom- 
erata. Both  senjavinensis  and  glomerata  exhibit  an  extreme  reduction  in  habit,  as  a 
result  of  the  arctic  conditions  under  which  they  grow,  so  that  they  are  closely  similar  in 
aspect,  but  they  are  not  sufficiently  close  in  other  features  to  justify  their  inclusion  in 
one  collective  species.  The  former  is  unique  in  the  extreme  development  of  the  long  and 
dense  villous  pubescence,  and  is  especially  distinct  from  glomerata  in  the  cut  of  the  leaf, 


66  GENUS   ARTEMISIA. 

as  shown  in  the  plates.  Their  occupation  of  the  same  general  region  (both  grow  around 
Kotzebue  Bay),  without  any  evident  tendency  towards  intergradation,  also  indicates 
that  they  are  not  directly  connected,  although  undoubtedly  of  the  norvegica-macrobotrys- 
laciniata  stock. 

ECOLOGY  AND  USES. 
Artemisia  senjavinensis  is  a  dwarf  mat-former  produced  by  extreme  Arctic  conditions, 
as  indicated  by  the  short  branches  and  coating  of  long  hairs.     No  uses  are  known  for  it. 

7.  ARTEMISIA  PARRYI  Gray,  Proc.  Am.  Acad.  7:361,  1868.     Plate  4. 

A  perennial  herb  with  a  rootstock,  1  to  4  dm.  high,  probably  without  strong  odor; 
stems  usually  in  groups,  simple  below,  erect,  glabrous,  faintly  striate,  seldom  if  ever 
reddish  tinged;  basal  and  lower  leaves  much  crowded,  petioled,  4  to  8  cm.  long  including 
petiole,  twice  pinnately  divided  into  linear  elongated  lobes,  the  divisions  either  widely 
spreading  or  ascending,  sparingly  pilose  especially  on  the  back  or  glabrous;  upper  leaves 
smaller  and  less  dissected  but  with  similar  elongated  linear  lobes  and  similar  pubescence ; 
inflorescence  an  elongated  terminal  raceme  or  branching  and  subpaniculate,  10  to  30  cm. 
long,  0.5  to  5  cm.  broad,  when  compound  the  branches  ascending;  heads  heterogamous, 
peduncled  (peduncles  1  to  5  mm.  long),  mostly  nodding;  involucre  hemispheric,  3  mm. 
high,  4  to  5  mm.  broad;  bracts  14  to  18,  elliptic,  obtuse,  brown  and  scarious  on  the 
margins,  glabrous  or  rarely  a  little  villous;  ray-flowers  about  8,  fertile,  corolla  tapering 
upwards,  about  1.5  mm.  long,  pubescent  or  glabrous;  disk-flowers  about  30  to  50,  fertile, 
corolla  funnelform,  about  2  mm.  long,  5-toothed,  pubescent  or  glabrous;  style-branches 
of  ray-flowers  acutish,  of  disk-flowers  truncate  or  rounded  and  erose  at  summit;  achenes 
nearly  cylindric  but  narrowed  below,  truncate  or  slightly  rounded  at  summit,  faintly 
4-  or  5-ribbed,  smooth  or  granuliferous. 

Known  only  from  the  high  mountains  of  southern  Colorado  and  southeastern  Utah. 
Type  locality,  Huerfano  Mountains,  Colorado  (erroneously  stated  by  Gray  to  be  in 
New  Mexico).  Collections:  Type,  September,  1867,  Parry  (Gr);  Colorado:  Sangre 
de  Cristo  Pass,  1867,  Parry  (Gr) ;  Crestones,  Sangre  de  Cristo  Mountains,  at  3,700  m. 
altitude,  Brandegee  (Gr,  UC  173290,  very  similar  to  the  type);  Cottonwood  Lake, 
Shear  3802  (NY) ;  La  Sal  Mountains,  near  Mount  Peal,  southeastern  Utah,  Rydberg  and 
Garrett  9003  (NY). 

SYNONYMS. 

1.  Artemisia  saxicola  parryi  Nelson;  Coulter  and  Nelson,  Man.  Rocky  Mt.  568,  1909. — Based  upon 
A.  parryi  Gray. 

RELATIONSHIPS. 

It  is  difficult  to  determine  the  exact  position  of  this  species  in  the  phylogenetic  scheme 
of  the  Artemisias.  This  is  due  to  its  scarcity,  its  local  distribution,  and  the  absence  of 
variations.  It  is  very  certain,  however,  that  it  belongs  to  the  group  of  macrobotrys 
and  norvegica,  and  although  not  heretofore  associated  taxonomically  with  the  former, 
it  seems  to  be  a  far  southern  representative  of  that  Siberian  and  Alaskan  species.  The 
heads  and  flowers  are  smaller  than  in  macrobotrys,  but  aside  from  this  and  a  certain 
leaf-character  there  are  no  essential  differences.  The  principal  reason  for  associating 
these  two  is  that  both  exhibit  a  unique  divergence  of  the  primary  divisions  of  the  leaf. 
In  macrobotrys  the  divisions,  at  least  of  the  lower  leaves,  stand  at  about  a  right  angle  to 
the  rachis.  An  equally  great  divergence  occurs  in  some  specimens  of  parryi,  for  example, 
Brandegee's  plant  from  Crestones,  Colorado  (Univ.  Calif.  Herb.  173290),  while  in  others 
the  divisions  are  directed  forward.  In  shape,  the  segments  are  quite  different.  Those 
of  macrobotrys  are  lanceolate  and  very  acute,  while  those  of  the  present  species  are 


A.    PARRYI — A.    STELLERIANA.  67 

strictly  linear,  the  sides  being  nearly  parallel,  and  the  apex  is  often  obtuse  or  only  barely 
acute.  If  the  assumption  is  correct  that  A.  parryi  is  an  ofifshoot  from  a  macrobotrys-like 
ancestor,  then  it  is  widely  separated  geographically  from  its  nearest  relatives.  It  is 
apparently  an  isolated  species  that  became  stranded  on  the  higher  peaks  of  the  southern 
Rocky  Mountains,  perhaps  during  one  of  the  migrations  of  the  glacial  period,  and  has 
there  developed  its  unique  characters.  More  copious  collections  are  much  needed 
and  especially  a  fuller  exploration  of  the  northern  Rocky  Mountains  in  order  to  discover 
forms  connecting  this  with  macrobotrys,  if  such  forms  exist. 

The  relationship  with  A.  norvegica  is  less  close.  It  is  difficult  to  prepare  a  key  that  will 
separate  parryi  from  all  of  the  variations  of  this  species,  but  each  of  the  subspecies 
differs  in  essential  characters.  The  only  one  that  inhabits  the  same  general  region  is 
saxatilis,  and  this  is  so  difTerent  in  its  large  heads,  with  numerous  large  flowers,  as  well 
as  in  the  foliage,  that  any  direct  phylogenetic  connection  is  out  of  the  question. 

Rydberg  has  recently  described  as  A.  cooleyae  a  new  species  which  he  places  next  to 
parryi,  apparently  considering  it  a  segregate  from  this.  It  is  discussed  in  the  present 
paper  among  the  minor  variations  of  A.  norvegica. 

ECOLOGY  AND  USES. 
Artemisia  parryi  is  a  rootstock  perennial,  forming  clans  in  the  subalpine  zone  in 
southern  Colorado  and  western  Utah.     It  is  too  infrequent  to  be  of  use. 

8.  ARTEMISIA  STELLERIANA  Besser,  Nouv.  Mem.  Soc.  Mosc.  3:79,  1834.    Plate  5. 
Beach  Sagewort. 

A  stout  perennial  herb,  from  a  creeping  cespitose  somewhat  woody  rootstock,  3  to  5 
dm.  high,  inodorous;  stems  crowded,  erect  or  the  base  decumbent,  simple  up  to  the 
inflorescence,  densely  white-tomentose  or  white-floccose,  striate;  basal  leaves  crowded, 
petioled,  3  to  8  cm.  long,  0.7  to  3  cm.  wide,  obovate  or  spatulate,  with  a  few  coarse  obtuse 
lobes  or  teeth  near  the  summit,  densely  white-tomentose  on  both  sides;  principal  and 
upper  leaves  sessile  or  subsessile,  2  to  6  cm.  long,  1.5  to  4  cm.  wide,  obovate  or  broadly 
oblanceolate  in  outline,  pinnately  lobed,  the  lobes  3  to  9,  elliptic  and  very  obtuse,  the 
whole  leaf  densely  white-tomentose  on  both  sides;  inflorescence  a  dense  panicle,  10 
to  20  cm.  long,  2  to  4  cm.  broad,  sometimes  almost  raceme-like;  heads  heterogamous, 
erect  or  nodding,  on  peduncles  2  mm.  or  less  long,  often  subsessile;  involucre  hemispheric, 
6  to  7  mm.  high,  6  to  9  mm.  broad;  bracts  9  to  12,  in  3  series,  the  outer  ones  broadly 
lanceolate  and  acute,  the  middle  ones  about  one-half  longer  and  obtuse,  the  innermost 
about  as  long  as  the  middle  series,  elliptic,  largely  scarious,  and  acute,  all  densely  tomen- 
tose  on  exposed  parts;  ray-flowers  7  to  12,  fertile,  corolla  subcylindric,  obscurely  2-toothed 
or  merely  erose  around  the  orifice,  2  to  2.5  mm.  long,  granuliferous;  disk-flowers  25  to 
40,  fertile,  corolla  trumpet-shaped,  3.5  to  4  mm.  long,  deeply  5-toothed,  resinous-granu- 
liferous;  style-branches  truncate,  erose  across  the  summit;  achenes  nearly  terete  but 
narrowed  at  base  and  slightly  rounded  to  the  summit,  glabrous. 

Sandy  shores  along  the  coast  from  Quebec  to  New  Jersey,  and  also  inland  from  Ontario 
to  New  York,  Wisconsin,  and  perhaps  elsewhere;  also  in  eastern  Asia  and  in  some  parts 
of  Europe.  Type  locality.  Port  of  Petropaulovski,  Kamchatka.  Collections:  Strand 
west  of  Riviere  Blanche,  Quebec,  Fernald  and  Collins  762  (Or) ;  sandy  seashore,  Falmouth, 
Massachusetts,  July  2,  1895,  Deane  (Gr) ;  sandy  shore,  Middletown,  Rhode  Island,  July  4, 
1909,  Williams  (Gr);  New  London,  Connecticut,  June  24,  1892,  Learned  (Gr);  sand  dunes. 
Five-mile  Beach,  New  Jersey,  MacElwee  IJ^I^l  (NY);  sandy  shore,  Oneida  Lake,  New 
York,  Haberer  2311  (Gr);  Sandy  Hook,  New  Jersey,  June  19,  1900,  Williams  (Gr); 
lake-shore  sands,  near  Port  Huron,  Michigan,  Dodge  5  (NY). 


68  GENUS   ARTEMISIA. 

RELATIONSHIPS. 

The  large,  heterogamous  heads  with  numerous  flowers,  the  fertile  achenes  in  both  ray 
and  disk,  and  the  absence  of  specialized  features  indicate  that  this  is  one  of  the  most 
primitive  of  Artemisias.  It  occurs  native  in  eastern  Siberia  and  is  apparently  not  far 
removed  phylogenetically  from  A.  vulgaris,  some  large-headed  forms  of  which  occupy 
the  same  phytogeographic  area.  The  American  species  which  it  most  closely  resembles 
is  A.  franserioides  of  the  southern  Rocky  Mountains,  and  since  this  species  has  no  close 
relatives  in  America  it  seems  not  impossible  that  it  is  an  offshoot  from  the  stelleriana 
stock.  The  agreement  between  the  two  in  essential  characters  and  somewhat  in  the  cut 
of  the  leaf  is  quite  close,  although  the  dissection  has  been  carried  much  farther  in  fran- 
serioides and  the  individual  flowers  are  reduced  in  size.  A.  stelleriana  appears  to  be  a 
non-plastic  species,  since  no  varieties  or  forms  have  been  described,  as  far  as  we  have 
been  able  to  learn. 

ECOLOGY  AND  USES. 

Artemisia  stelleriana  is  a  perennial  herb  with  creeping  rootstocks,  which  forms  consocies 
on  sandy  shores  and  on  dunes,  often  covering  extensive  areas  as  a  pure  community. 
It  has  generally  been  assumed  to  be  an  escape  from  cultivation,  in  all  its  European  and 
American  stations  (Fernald,  Rhodora  2:38,  1900),  but  it  is  a  puzzling  fact  that  it  has 
always  escaped  into  the  sands  of  seashores  and  lake-shores,  and  apparently  never  into 
roadsides  and  waste  places. 

The  remarkably  white  herbage  gives  to  this  species  a  certain  value  as  an  ornamental 
plant.  It  is  therefore  grown  to  a  limited  extent  both  in  American  and  European  gardens, 
more  especially  for  borders.     Beyond  this  it  is  of  no  economic  value. 

9.  ARTEMISIA  ALASKANA  Rydberg,  N.  Am.  Fl.  34:281,  1916.     Plate  5. 

A  perennial  herb  or  perhaps  shrubby  at  base,  the  lower  portions  not  present  on  the 
single  specimen  thus  far  collected,  4  dm.  or  more  high,  the  odor  not  known;  stems  appar- 
ently crowded  at  the  base  to  form  a  tussock  or  close  clump,  mostly  erect,  simple  except 
below  and  in  the  inflorescence,  striate,  sparingly  tomentulose;  lower  leaves  crowded, 
petioled,  3  to  5  cm.  long,  1.5  to  4  cm.  wide  across  the  lobes,  twice  dissected,  first  pinnate 
into  3  to  5  divisions,  each  of  which  is  irregularly  again  cleft,  or  some  leaves  twice  ternate, 
the  ultimate  segments  oblong  or  linear,  obtuse,  0.4  to  2  cm.  long,  2  mm.  or  less  wide, 
the  whole  leaf  appressed  silvery-tomentose  on  both  sides;  upper  leaves  5  to  6  cm.  long, 
mostly  with  1  or  2  linear  lateral  lobes  and  a  3-cleft  terminal  one,  or  simply  ternate,  the 
lobes  linear  and  obtuse,  silvery-tomentose  like  the  lower,  the  leaves  of  the  inflorescence 
ternately  cleft  to  entire  and  scarcely  reduced  in  length ;  inflorescence  a  very  open  raceme, 
or  subpaniculate  below,  leafy  throughout,  25  to  30  cm.  long,  4  to  6  cm.  broad;  heads 
heterogamous,  on  peduncles  1  to  7  cm.  long,  erect  or  nodding;  involucre  hemispheric, 
4.5  to  5  mm.  high,  6  to  7  mm.  broad;  bracts  about  15  to  20  in  addition  to  a  few  linear 
subtending  bracts  of  the  peduncle,  elliptic  or  ovate,  obtuse,  with  broad  scarious  erose 
margins,  villous-tomentose;  ray-flowers  7  to  16,  fertile,  corolla  tubular,  1.5  to  2  mm. 
long;  disk-flowers  about  50  to  60,  fertile,  corolla  funnelform,  5-toothed,  2  to  2.5  mm.  long, 
glandular-granuliferous  below;  style  of  ray-flowers  linear,  obtuse,  of  disk-flowers  flat, 
strongly  recurved,  penicillate  at  the  truncate  apex;  achenes  nearly  prismatic,  truncate 
at  summit,  faintly  angled,  glabrous. 

Known  only  from  the  type  collection,  between  Nulata  and  Nowikakat,  on  the  Yukon 
River,  west-central  Alaska,  July  23  to  27,  1889,  Russell  (US). 

RELATIONSHIPS. 

The  close  relationship  between  this  form  and  the  Siberian  A.  iurczaninoviana  Besser 
was  suggested  by  Rydberg  in  connection  with  his  original  diagnosis.     The  similarity 


A.    ALASKANA — A.    FRANSERIOIDES.  0\) 

between  the  two  is  so  close  that  future  collections  in  the  intervening  territory  will  probably 
demonstrate  the  presence  of  intermediate  forms.  The  chief  differences,  as  far  as  indicated 
by  the  scant  material  at  hand,  are  the  following : 

Artemisia  turczaninoviana.  Artemisia  alaskana. 

Leaves  of  the  inflorescence  reduced,  1  cm.  or  less  long.  Leaves  of  the  inflorescence  elongated,  mostly  2  to  6 

cm.  long. 
Peduncles  less  than  1  cm.  long,  all  simple.  Peduncles  1  to  7  cm.  long,  the  lower  ones  branched. 

Involucre  3  mm.  or  less  high.  Involucre  about  5  mm.  high. 

While  the  differences  here  indicated  will  serve  to  distinguish  the  two  forms  as  now 
represented  in  herbaria,  it  will  be  noticed  that  they  are  all  based  upon  characters  which 
in  other  groups  are  found  to  undergo  a  wide  range  of  variation  when  a  large  series  of 
specimens  is  available  for  study.  There  are  no  constant  differences  in  size  or  number 
of  flowers  in  the  head.  A  serious  objection  to  the  reduction  of  alaskana  to  a  subspecies 
of  turczaninoviana  is  the  relation  of  the  latter  to  the  still  older  A.  rutaefolia  Stephani  and 
its  variation  A.  kruhsiana  Besser,  both  natives  of  Siberia.  These  are  supposed  to  differ 
in  their  ternate  instead  of  pinnatifid  leaves,  but  this  is  a  variable  feature.  Besser's 
plate  of  turczaninoviana  (Besser,  Nouv.  Mem.  Soc.  Imp.  Nat.  Mosc.  3:plate  1,  1834), 
as  also  nearly  all  authentic  specimens  at  hand,  has  some  leaves  which  are  once  or  twice 
ternate,  while  on  the  same  stems  some  are  first  pinnate  and  with  the  primary  divisions 
with  2  or  3  lobes.  Probably  more  important  are  the  circumscription  of  the  entire  leaf 
and  the  shape  of  the  segments.  The  ultimate  divisions  are  obovate-lanceolate  in 
rutaefolia,  cuneate  in  kruhsiana,  narrowly  oblong  to  linear  in  turczaninoviana  and  alaskana. 
It  is  probable  that  a  complete  series  will  ultimately  be  found.  In  the  meantime,  it 
seems  less  likely  to  lead  to  confusion  to  retain  alaskana  as  a  distinct  species,  while  indicat- 
ing its  close  relationship  to  these  Siberian  forms.  It  is  not  directly  connected  with  any 
other  American  Artemisia. 

ECOLOGY  AND  USES. 

Nothing  is  known  of  the  ecology  or  uses  of  this  rare  species. 

10.  ARTEMISIA  FRANSERIOIDES  Greene,  BuU.  Terr.  Club  10:42, 1883.     Plate  6. 
Forest  Sagewort. 

A  perennial  herb  from  short  creeping  rootstocks,  3  to  10  dm.  high,  pleasantly  fragrant 
with  a  sweet  heavy  odor;  stems  clustered,  erect,  simple  up  to  the  inflorescence,  conspic- 
uously grooved,  tomentulose  when  young  but  glabrate  except  towards  the  summit, 
reddish  tinged  at  maturity;  basal  leaves  at  first  forming  rosettes  but  not  crowded, 
petioled  (the  petioles  1  to  5  cm.  long),  the  blade  4  to  7  cm.  long,  3  to  6  cm.  wide,  subor- 
bicular  or  ovate  in  outline,  pinnately  divided  into  5  to  9  elliptic  or  oblanceolate  divisions 
which  are  again  cleft  or  divided  into  oblong  or  oblanceolate  entire  or  toothed  obtuse 
divisions,  glabrous  or  minutely  puberulent  above,  finely  but  densely  gray-tomentulose 
beneath;  principal  and  upper  leaves  like  the  lower,  but  becoming  gradually  smaller, 
less  dissected,  and  shorter  petioled;  inflorescence  a  lax  narrow  panicle,  15  to  40  cm.  long, 
1  to  4  cm.  broad,  the  heads  notably  secund  on  the  branches,  rarely  reduced  and  raceme- 
like; heads  heterogamous,  nodding,  on  peduncles  1  to  4  mm.  long;  involucre  hemispheric, 
2.5  to  3  mm.  high,  about  5  mm.  broad;  bracts  9  to  15,  nearly  equal,  narrowly  to  broadly 
elliptic  or  oblong,  very  obtuse,  brownish  or  greenish  yellow,  with  a  narrow  erose  scarious 
border,  finely  tomentulose,  sometimes  glabrate;  ray-flowers  6  to  13,  fertile,  corolla  nar- 
rowly tubular,  about  1.5  mm.  long,  the  orifice  contracted  and  scarcely  toothed,  granu- 
liferous;  disk-flowers  45  to  90,  fertile,  corolla  narrowly  campanulate,  1.5  to  2  mm.  long, 
5-toothed,  resinous-granulif erous ;  style-branches  truncate,  erose  at  the  summit;  achenes 
nearly  cylindric,  truncate  and  with  a  raised  border  at  the  broad  summit,  faintly  nerved, 
glabrous. 


70  GENUS  ARTEMISIA. 

Southern  Rocky  Mountains  at  more  than  middle  altitudes  (chiefly  in  the  Canadian 
Zone) :  Colorado,  New  Mexico,  Arizona,  and  Chihuahua.  Type  locality,  in  deep  shady 
woods  of  Pseudotsuga  near  the  summits  of  the  Pinos  Altos  Mountains,  New  Mexico. 
Collections:  Colorado,  Rio  La  Plata,  near  Parrott  City,  September,  1875,  Brandegee 
(UC);  Lake  Creek,  Sangre  de  Cristo  Range,  at  2,750  m.  altitude,  August,  1874,  Brandegee 
(UC) ;  near  Pagosa  Peak,  Baker  632  (Gr,  NY) ;  San  Juan  Mountains,  on  both  sides  of 
Wolf  Creek  Pass,  Clements  and  Hall  11106  and  IIII4  (UC);  Roubadeaux  Pass,  Rocky 
Mountains,  Kreuerfeldt  in  Gunnison's  Expedition  37  (Gr);  White  Mountains,  New 
Mexico,  at  2,300  m.  altitude,  Wooton  34?  (Gr,  NY,  UC) ;  type  collection,  September  15, 
1880,  Greene  (Gr,  UC,  the  latter  labeled  October  14,  1880);  Huachuca  Mountains,  Ari- 
zona, Goodding  855  (NY) ;  Mount  Graham,  southern  Arizona,  September,  1874,  Rothrock 
753  (Gr);  Sierre  Madre,  Chihuahua,  at  3,000  m.  altitude,  Pringle  2013  (UC,  NY). 
RELATIONSHIPS. 

In  gross  aspect  Artemisia  franserioides  is  more  hke  certain  forms  of  A.  vulgaris  than 
any  other  American  species.  It  differs  from  all  of  these,  however,  in  the  bipinnately 
divided  foliage  with  obtuse  lobes  and  in  the  remarkably  secund  inflorescence,  this  latter 
a  unique  feature  in  this  section  of  the  genus.  Its  connection  with  vulgaris  would 
naturally  be  sought  through  one  of  the  southern  subspecies  (it  has  been  several  times 
mistaken  for  A.  vulgaris  discolor),  but  these  all  differ  in  having  undergone  a  considerable 
reduction  in  the  number  of  disk-flowers,  none  having  more  than  about  20  in  a  head, 
while  franserioides  has  47  to  90  or  more.  Since  its  other  characters  are  also  at  con- 
siderable variance  with  all  of  the  subspecies  of  the  main  branch  of  vulgaris,  as  diagramed 
in  figure  9,  it  is  not  desirable  to  invoke  reversion  to  account  for  this  large  number. 
It  is  more  likely  that  franserioides  is  a  descendant  from  a  more  primitive  type  than  any  of 
the  forms  just  mentioned.  Perhaps  this  ancestor  is  not  represented  by  existing  species, 
but  it  is  interesting  to  note  the  similarity  between  franserioides  and  stelleriana,  as  has 
been  already  mentioned  under  the  latter  species.  These  two  are  so  closely  similar  in 
technical  characters  and  in  the  obtuse  nature  of  the  leaf-lobes  that  their  derivation  from 
the  same  stock  seems  quite  likely.  A.  stelleriana  is  native  in  eastern  Siberia  where  other 
similar  species  occur,  such  as  turczaninoviana  and  rutaefolia.  In  any  case,  the  parent 
form  of  A.  franserioides  was  undoubtedly  an  inhabitant  of  the  far  north,  and  franserioides 
is  therefore  to  be  looked  upon  as  a  remnant  stranded  on  the  high  mountains  of  the 
southern  United  States  and  northern  Mexico. 

This  species  is  fairly  constant  in  vegetative  characters  and  in  those  of  the  involucre 
and  flowers,  as  is  shown  in  table  5  (page  72).     This  is  in  agreement  with  most  other 
species  of  limited  distribution  and  at  the  same  time  well  separated  phylogenetically. 
ECOLOGY  AND  USES. 

Artemisia  franserioides  is  a  rootstock-perennial,  which  forms  clans  in  shady  openings 
in  forest  of  aspen  or  Douglas  spruce,  where  it  is  associated  with  Epilobium  spicatum, 
Berberis  aquifolium,  Thalictrum  fendleri,  Fragaria  vesca,  Geranium  caespitosum,  and 
Artemisia  dracunculus.  The  flowers  bloom  from  August  to  late  September.  No  uses 
are  known  for  this  species. 

11.  ARTEMISIA  VULGARIS  Linnaeus,  Sp.  PI.  848,  1753.  Plates  6  to  9.  Sagewort; 
Mug  WORT. 
A  perennial  herb,  sometimes  suffruticose  at  base,  from  a  creeping  rootstock,  3  to  20 
dm.  high,  with  a  peculiar  pungent  odor;  stems  either  scattered  or  more  commonly  growing 
in  close  formation,  sometimes  clustered  on  short  caudex-like  rootstocks,  erect,  simple 
up  to  the  inflorescence,  striate  or  shallowly  grooved,  cinereous-tomentose  to  glabrous, 
often  reddish  tinged  in  age;  basal  leaves  not  crowded,  petioled,  6  cm.  or  less  long,  from 
shallowly  toothed  near  the  summit  to  twice  pinnately  dissected,  white-tomentose  at 
least  beneath;  principal  and  upper  leaves  exceedingly  various  in  outUne  and  lobing, 


A.    VULGARIS.  71 

from  entire  to  twice  dissected,  the  upper  surface  glabrous  to  densely  and  permanently 
white-tomentose,  the  lower  surface  always  white-tomentose;  inflorescence  paniculate, 
10  to  40  cm.  long,  usually  2  to  8  cm.  broad  but  sometimes  reduced  to  a  spike  only  1  cm. 
broad  or  again  with  spreading  branches  and  then  up  to  15  or  20  cm.  broad;  heads  hetero- 
gamous,  short-peduncled  or  sessile,  nodding  or  erect;  involucre  campanulate  to  ovoid, 
3  to  5  mm.  high,  2  to  8  mm.  broad;  bracts  7  to  16,  ovate  or  broadly  elliptic,  obtuse,  with 
pale  or  light-brown  scarious  margins,  densely  tomentose  to  glabrous;  ray-flowers  4  to  10, 
fertile,  corolla  narrowed  and  irregularly  toothed  above,  1.5  to  2  mm.  long,  glabrous  or 
resinous-granulif erous ;  disk-flowers  3  to  50,  fertile,  corolla  funnelform,  1.5  to  3  mm.  long, 
5-toothed,  glabrous  or  only  resinous-granulif  erous ;  style-branches  truncate  or  obtuse, 
those  of  the  disk-flowers  dilated  and  erose  at  summit;  achenes  ellipsoid,  not  nerved  or 
angled,  glabrous  but  often  resinous-glandular. 

Almost  throughout  North  America;  common  also  in  the  Old  World. 
SUBSPECIES. 

No  other  Artemisia  has  such  a  multitude  of  variations  as  A.  vulgaris.  Many  of  these 
result  from  environmental  influences;  in  others,  individual  variation  is  so  great  that  a  taxo- 
nomic  analysis  becomes  impossible.  The  American  forms  may  be  assembled  into  15  sub- 
species, as  follows: 

Key  to  the  Subspecies  oj  Artemisia  vulgaris. 
Involucre  4  to  5  mm.  high,  4  to  8  mm.  broad;  disk-flowers  20  to  50.     Northwestern  forms. 
Foliage  green  above,  densely  white-tomentose  beneath;  involucre  sparsely  tomentose, 

greenish (a)  tilesi  (p.  72). 

Foliage  white-tomentose  on  both  sides,  sometimes  less  densely  so  above;  involucre 

densely  tomentose (6)  candicans  (p.  73). 

Involucre  3  to  4  mm.  high,  2  to  4  mm.  broad;  disk-flowers  3  to  20,  or  occasionally  to  25  (in 
heterophylla  and  longifolia,  and  even  to  50  in  discolor,  which  con- 
nects through  large-headed  forms  with  tilesi). 
Divisions  of  lower  leaves  again  toothed  cleft  or  lobed;  divisions  of  middle  stem-leaves 
also  usually  toothed  or  cleft. 
Leaves  green  and  nearly  glabrous  above,  white-tomentose  beneath. 

Primary  divisions  of  leaves  5  to  15  mm.  wide,  directed  forward (c)   lypica  (p.  73). 

Primary  divisions  of  leaves  less  than  5  mm.  wide,  spreading. 

Panicle  5  cm.  or  less  broad,  compact;  heads  mostly  20-  to  50-flowered (d)  discolor  (p.  74). 

Panicle  10  to  15  cm.  broad,  with  spreading  leafy  branches;  heads  15-  to  20- 

flowered (e)   reddens  (p.  75). 

Leaves  white-tomentose  on  both  sides (/)  flodmani  (p.  75). 

Divisions  of  all  the  leaves  entire  or  nearly  so  or  leaves  themselves  entire. 
Leaves  ample,  principal  ones  1  to  2.5  cm.  or  more  wide,  with  a  few  prominent  lanceo- 
late lobes,  varying  to  entire,  upper  surface  green;  involucre  3  to  4 
mm.  high. 
Disk-flowers  9  to  23;   involucre    campanulate,  2.5  to  3.5   mm.  broad,  densely 

tomentose {g)  kelerophylla  (p.  76). 

Disk-flowers  3  to  7;  involucre  ovoid,  2  to  2.5  mm.  broad,  nearly  glabrous (h)  litoralis  (p.  76). 

Leaves  narrow,  1  cm.  or  less  wide  exclusive  of  lobes  when  present,  divisions  also  nar- 
row, upper  surface  either  green  or  gray-tomentose;  involucre  rarely 
over  3  mm.  high  except  in  subspecies   gnaphalodes   and  longifolia. 
Principal  leaves  entire  or  variously  toothed,  cleft,  or  rarely  divided  but  the  lobes  * 

not  slender  and  elongated  (except  in  a  rare  form  of  longifolia,  with 
lobes  caudate-attenuate). 
Inflorescence  plainly  paniculate,  1.5  cm.  or  more  broad. 
Margins  of  leaves  not  evenly  serrate. 
Upper  surface  of  leaves  more  thinly  tomentose  than  lower  or  at  length 

glabrate  and  green (i)   ludoviciana  (p.  76). 

Upper  surface  of  leaves  densely  white-tomentose  Uke  lower,  tomentum 
usually  psrsistent  (exceptions  in  longifolia  are  recognized  by  the 
caudate  leaves). 
Involucre  3  to  3.5  mm.  high;  leaves  not  very  slender,  entire  or  with 

comparatively  short  lobes (j)    gnaphalodes  (p.  77). 

Involucre  about  4  mm.  high;  leaves  slender  and  elongated,  often  caudate- 
attenuate,  entire  or  divided  into  similarly  elongated  lobes (k)  longifolia  (p.  78). 

Margins  of  leaves  evenly  serrate (I)    serrata  (p.  79). 

Inflorescence  a  narrow  spike-like  panicle  1  cm.  or  less  broad.     A  low  plant, 
often  woodv  below,  with  narrow  leaves  inclined  to  be  entire  or  only 

slightly  lobed (m)  lindleyana  (p.  79). 

Principal  leaves  mostly  divided  into  slender  elongated  or  hnear-filiform  lobes 
4  mm.  or  less  wide. 

Leaf-lobes  mostly  2  to  4  mm.  wide (n)  mexicana  (p.  80). 

Leaf-lobes  0.5  to"  1  mm.  wide (o)  wrighti  (p.  80). 


72 


GENUS   ARTEMISIA. 


11a.  Artemisia  vulgaris  tilesi  (Ledebour). — Stems  2  to  6  dm.  high,  from  rootstocks; 
lower  leaves  ovate  in  outline,  cut  nearly  to  the  midrib  into  unequal  lobes,  these  often 
again  cleft  or  toothed;  principal  leaves  ovate  or  broadly  elliptic  in  outline,  7  to  17  cm. 
long,  3  to  7  cm.  wide,  cleft  more  than  half-way  to  the  midrib  into  unequal  segments 
which  are  either  entire  or  with  a  few  lobes  or  teeth,  both  primary  and  secondary  lobes 
all  pointing  forward  and  acute  or  acuminate  (except  in  an  occasional  plant,  as  in  A.  tilesi 
arctica  Besser,  minor  variation  84,  in  which  the  lobes  are  broad  and  obtuse),  the  leaves 
of  the  inflorescence  less  cut  or  often  entire,  all  leaves  green  and  glabrous  or  only  puberu- 
lent  above,  densely  and  permanently  white-tomentose  beneath,  the  margins  narrowly 
revolute;  inflorescence  in  the  original  form  dense,  spike-like,  0.5  dm.  or  less  long  by  about 
2  cm.  broad,  commonly  overtopped  by  the  leaves,  but  in  the  more  common  form  (minor 
variation  85,  A.  tilesi  elatior  Torrey  and  Gray)  the  inflorescence  an  elongated  panicle  1 
to  3  dm.  long  by  2  to  6  cm.  broad  and  much  exceeding  the  leaves;  involucre  hemispheric, 
4  to  5  mm.  high,  5  to  8  mm.  broad,  glabrous  and  green  or  yellowish  to  puberulent  and 
more  or  less  canescent,  or  reddish,  mostly  30-  to  70-flowered.  {A.  tilesi  Ledebour,  Mem. 
Acad.  St.  Petersb.  5:568,  1805.) 


Table  5. — Variation  in  Artemisia  franserioides. 


Rio  La  Plata,  Southwestern  Colo. 
Sangre  de  Cristo  Range,  Colo.  .  . . 

White  Mountains,  N.  Mex 

Sierra  Madre,  Chihuahua 

Same  collection 

San  Juan  Mountains,  Colo 


Do. 


172715  UC 
173319  UC 
135385  UC 
34329  UC 
91232  UC 
205741  UC 
205740  UC 

172707  UC 


5.0 
4.5 
5.0 
5.0 
5.0 
5.0 
5.0 


9  11 
11  9 
14  11 

14  13 
11  12 

15  13 
14  12 

11  12 


50  54 
60  50 
65  48 
55  47 
48  53 
91  61 

58  60 

59  83 


Length 
of  disk- 
coroUaa. 


Eastern  Siberia  and  arctic  North  America  east  at  least  to  Hudson  Bay,  south  to  Mon- 
tana, northeastern  Nevada,  and  Oregon.  Type  locality,  Kamchatka.  Collections:  King 
Point,  Arctic  America,  June  28,  1906,  Lindstrom  (NY);  Arctic  shore  between  Mackenzie 
and  Coppermine  Rivers,  Richardson  (NY,  variation  84  with  short,  obtuse  leaf-lobes, 
A.  tilesi  arctica  Besser);  vicinity  of  Norton  Sound,  Alaska,  1899,  Rhodes,  Newhall,  and 
Giacomini  (UC);  vicinity  of  Norton  Sound,  Alaska,  1900,  MacGregor  (UC,  typical); 
St.  Paul  Island,  Bering  Sea,  Macoun  94006  (Or) ;  St.  Lawrence  Island,  Bering  Sea,  August 
15,  1891,  Macoun  (Or);  Arakamtchetchene  Island,  Bering  Straits,  1853-56,  Wright  (Gr); 
Unalaska,  Bering  Sea,  Macoun  20625  (NY,  type  collection  of  A.  unalaskensis  Rydberg, 
minor  variation  87) ;  Lake  Iliamna  Region,  Alaska,  Gorman  281  (Gr,  NY,  US,  type  col- 
lection of  A.  gormani  Rydberg,  minor  variation  24);  White  Pass,  Yukon,  Eastwood  899 
(SF) ;  Skaguay,  Alaska,  Eastwood  772  (SF) ;  Nome,  Alaska,  Blaisdell  80  (NY,  UC,  minor 
variation  24,  A.  gormani  Rydberg);  Dawson,  Canada,  Eastwood  455  (SF);  Churchill, 
Hudson  Bay,  Macoun  79263  (Gr,  with  small  heads  and  narrow  inflorescence  of  minor 
variation  85,  A.  tilesi  elatior  Torrey  and  Gray,  but  the  inflorescence  leafy);  ChiUiwack 
Valley,  British  Columbia,  Spreadbrough  (Geological  Survey  of  Canada  76930,  NY); 
Stehekin,  eastern  Washington,  Griffiths  195  (NY,  minor  variation  85,  A.  tilesi  elatior 
Torrey  and  Gray);  Chiwankum  Lake,  Wenatchee  Forest,  Washington,  Eggleston  13597 


A.    VTJLGAEIS.  73 

(US);  Cascade  Mountains,  49°  N.  lat.,  Oregon,  1859,  Lyall  (Gr,  minor  variation  85,  A. 
tilesi  elatior  Torrey  and  Gray);  Wallowa  Mountains,  Oregon,  Piper  2491  (Gr,  same 
variation) ;  Martin  Creek,  Elko  County,  Nevada,  Kennedy  4S74.  (UC,  same  variation) ; 
Bozeman  Canon,  Montana,  Rydberg  294S  (NY,  same  variation). 

116.  Artemisia  vulgaris  candicans  (Rydberg). — Stems  5  to  15  dm.  high,  leafy, 
from  strong  rootstocks,  forming  small  bush-like  clumps  or  thickets;  lower  leaves  obovate 
or  broadly  oblong,  from  deeply  cut  into  spreading  lanceolate  lobes  which  are  typically 
again  lobed  or  toothed  to  shallowly  and  obtusely  few-lobed;  principal  leaves  obovate  or 
oblanceolate  or  broadly  elliptic  in  outUne,  4  to  10  cm.  long,  1.5  to  4  cm.  wide,  pinnatifid 
or  divided  into  oblong  or  lanceolate  often  again  cleft  segments,  these  more  or  less  diver- 
gent or  in  some  forms  the  leaves  with  only  a  few  short  coarse  teeth  or  shallow  lobes  and 
some  nearly  entire  (minor  variation  61,  J.,  platyphylla  Rydberg),  those  of  the  inflores- 
cence less  lobed  to  entire,  all  leaves  densely  white-tomentose  on  both  sides,  but  especially 
beneath,  the  margins  very  narrowly  revolute;  inflorescence  a  cylindric  panicle,  sometimes 
divided  into  short,  dense  glomerules  (the  typical  form)  or  more  open  by  the  elongation  of 
the  peduncles  (minor  variation  19,  A.floccosa  Rydberg),  2  to  4  cm.  broad;  involucre  hemi- 
spheric, about  4  to  5  mm.  high,  4  to  7  mm.  broad,  tomentose,  20-  to  50-flowered  {A.  can- 
dicans Rydberg,  Bull.  Torr.  Club  24:296,  1897).  Montana  to  western  Wyoming,  Idaho 
and  eastern  Oregon  and  Washington.  Type  locality.  Little  Belt  Mountains,  Montana. 
Collections:  Type  collection,  August  18,  1896,  Flodman  882  (NY,  US);  Lima,  Montana, 
Rydberg  29^2  (NY,  US,  type  of  A.  floccosa  Rydberg,  minor  variation  19);  Cliff  Creek, 
Wyoming,  August,  1900,  Curtis  (NY);  Yellowstone  Lake,  Wyoming,  Nelson  6612  (R, 
type  of  A.  gracilenta  Nelson,  minor  variation  25);  Gilmore,  in  the  Lemhi  Range  of 
eastern  Idaho,  Hall  11548  (UC);  near  Prineville,  Oregon,  Leiberg  801  (NY);  Spokane 
River  at  Spokane,  Washington,  Elmer  867  (NY,  type  collection  of  A.  platyphylla  Ryd- 
berg, minor  variation  61);  same  locality,  September  and  October,  1921,  Moore  (UC,  a 
large  series  of  leaf-variations  connecting  candicans  and  platyphylla). 

lie.  Artemisia  vulgaris  typica. — Stems  erect,  5  to  15  dm.  high,  from  shallow  root- 
stocks,  often  growing  in  small  clumps;  lower  leaves  obovate,  cut  nearly  to  the  midrib 
into  unequal  lobes  with  toothed  or  incised  margins;  principal  leaves  obovate,  broadly 
elliptic  or  oblanceolate  in  outline,  5  to  10  cm.  long,  3  to  7  cm.  wide,  cleft  nearly  to  the 
midrib  into  unequal  segments  (the  terminal  much  the  largest)  which  are  again  irregularly 
toothed  or  more  deeply  cleft,  the  lobes  and  teeth  all  pointing  forwards  and  approximate, 
the  leaves  of  the  inflorescence  simply  pinnatifid  to  entire,  all  leaves  smooth,  green  and 
glabrous  or  nearly  so  above,  densely  and  permanently  white-tomentose  beneath,  the  mar- 
gins obscurely  revolute;  inflorescence  an  ample  branching  leafy  panicle  with  ascending 
branches  along  which  the  heads  are  disposed  in  glomerules,  4  to  20  cm.  broad  (occa- 
sionally reduced  to  a  single  compact  panicle  about  3  cm.  broad) ;  involucre  campanulate, 
3.5  to  4  mm.  high,  2.5  to  3.5  mm.  broad,  cinerous-tomentose,  15-  to  25-flowered.  {A. 
vulgaris  Linnaeus,  Sp.  PI.,  848,  1753.)  Widely  distributed  in  the  Old  World;  probably 
introduced  in  America,  where  it  now  grows  at  many  places  from  Newfoundland  to 
Georgia,  Alabama,  Wisconsin,  Manitoba,  and  Ontario;  also  in  British  Columbia  and 
on  Martinique.  Type  locaUty:  Europe.  Collections:  Prince  County,  Prince  Edward 
Island,  Fernald,  Long,  and  St.  John  8231  (Gr);  Nova  Scotia,  Howe  and  Lang  157  (NY); 
Birchy  Cove,  western  Newfoundland,  on  rubbish  heaps,  Fernald  and  Wiegand  4167 
(Gr);  Yarmouth,  St.  John  River,  at  St.  Francis,  Maine,  Fernald  70  (Gr,  NY,  UC,  US); 
Point  Edward,  Lake  Huron,  Ontario,  Macoun  26353  (US);  New  Haven,  Connecticut, 
September  28,  1886,  Setchell  (UC);  near  Andover,  New  Jersey,  September  26,  1887, 
Britton  (UC);  Rochester,  New  York,  August  16,  1917,  House  (Gr);  Detroit,  Michi- 
gan, September  1,  1915,  Chandler  (US);  Lake  Vadnais,  Ramsey  County,  Minnesota, 


74 


GENUS   ARTEMISIA. 


Sandberg  711  (US);  Brunswick,  Glynn  County,  Georgia,  Harper  1527  (Gr,  NY,  US); 
Linnton,  Oregon,  J.  C.  Nelson  837  (Gr);  flood  plain  of  the  Columbia  River,  British 
Columbia,  Shaw  1170  (US);  vicinity  of  St.  Pierre,  Martinique,  Pere  Dussl737, 1^075  (US). 


Fio.  7. — A  comparison  of  leaf-outlines  of  Arlemisia  vulgaria  typica  and  A.  v.  heterophylla:  a,  b,  c,  d,  leaves  of  typica  from  one 
plant  in  the  Botanical  Garden  of  the  University  of  California;  e,  /,  g,  h,  i,  leaves  of  heterophylla  from  one  plant 
in  the  Oakland  Hills,  California.     All  X  0.5 


lid.  Artemisia  vulgaris  discolor  (Douglas). — Stems  erect,  2  to  8  dm.  high,  from 
horizontal  sometimes  suffrutescent  rootstocks;  lower  leaves  obovate  or  oblanceolate,  cut 
nearly  to  the  midrib  into  spreading  divisions  which  are  again  toothed  or  more  deeply 
lobed;  principal  leaves  obovate  or  broadly  elliptic  in  outline,  2  to  8  cm.  long,  1  to  4  cm. 
wide,  dissected  nearly  to  the  midrib  into  linear  or  lanceolate  lobes,  these  either  entire, 
toothed,  or  lobed,  the  leaves  toward  the  inflorescence  simply  cleft  or  entire,  all  green  and 
glabrous  or  glabrate  above,  densely  to  sparsely  white-tomentose  beneath,  the  margins 
commonly  revolute;  inflorescence  a  compact  panicle,  sometimes  raceme-like,  1  to  3  cm. 
broad  or  much  broader  when  composed  of  racemiform  branches;  involucre  campanula te, 
3.5  to  4  mm.  high,  2  to  4  mm.  broad,  very  sparsely  tomentose  and  glabrate  or  glabrous 
from  the  beginning,  yellowish-green,  somewhat  shining,  20-  to  50-  flowered.  {A.  dis- 
color Douglas  in  Hooker,  Fl.  Bor.  Am.  1:322,  as  synonym,  1833;  Besser,  Bull.  Soc.  Nat. 
Mosc.  9:46,  1836.)  The  three  most  notable  variations  under  this  subspecies  are  diag- 
nosed under  A.  michauxiana,  page  84,  and  specimens  belonging  to  them  are  indicated  in 
the  following  citations.  Saskatchewan  and  Montana  to  Colorado,  the  Sierra  Nevada  of 
California,  and  British  Columbia.  Type  locality,  near  Spokane  and  Kettle  Falls, 
Washington.  Collections:  Lake  Louise  region,  Alberta,  Rosendahl  1097  (NY,  minor 
variation  53,  A.  michauxiana  Besser);  Bridger  Mountains,  Montana,  August  21,  1902, 
W.  W.  Jones  (DS,  UC,  US,  genuine);  Long  Baldy,  Little  Belt  Mountains,  Montana, 


A.    VULGARIS.  75 

Flodman  881  (NY,  US,  type  collection  of  A.  graveolens  Rydberg,  minor  variation  26); 
Emigrant  Gulch,  Montana,  Rydberg  and  Bessey  5201  (NY,  US,  type  collection  of  A. 
tenuis  Rydberg,  minor  variation  80);  same  locality  and  collectors,  5201a  (NY,  US,  type 
collection  of  A.  tenuis  integerrima  Rydberg,  minor  variation  81);  same  locality  and  col- 
lectors, 520S  (Gr,  NY,  minor  variation  30,  A.  incompta,  Nuttall);  Thornberg's  Pass, 
southern  Idaho,  Nuttall  (Gr,  Phila,  type  collection  of  A.  incompta  Nuttall);  Mackay, 
Idaho,  Nelson  and  Macbride  1521  (DS,  Gr,  US,  minor  variation  26,  A.  graveolens  Ryd- 
berg); Doyle  Creek,  Wyoming,  Goodding  385  (NY,  UC,  US,  similar  variation);  Anita 
Peak,  northwestern  Colorado,  Goodding  1753  (Gr,  NY,  minor  variation  30,  A.  incompta 
Nuttall) ;  head  of  Bullion  Creek,  Marysvale,  Utah,  Jones  5873  (UC,  genuine) ;  Humboldt 
Canon,  West  Humboldt  Mountains,  Nevada,  Heller  10625  (DS,  Gr,  NY,  UC,  minor 
variation  26,  A.  graveolens  Rydberg);  trail  to  Mount  Whitney,  California,  Culbertson 
4341  (UC,  genuine);  near  Summit,  Placer  County,  California,  Heller  12898  (SF,  UC, 
minor  variation  30,  A.  incompta  Nuttall) ;  base  of  Steins  Mountains,  Oregon,  Cusick  1990 
(UC,  form  with  inflorescence  as  in  genuine  discolor  but  foliage  as  in  minor  variation  53, 
A.  michauxiana  Besser;  specimens  of  this  and  the  next  in  other  herbaria  are  not  as 
here  indicated);  Steins  Mountains,  Oregon,  Cusick  1991  (UC,  A.  michauxiana  Besser, 
both  as  to  foliage  and  inflorescence);  fissures  of  dry  rocks  near  the  Kettle  Falls  and 
sources  of  the  Columbia  River,  1826,  Douglas  (NY,  from  type  of  A.  michauxiana  Besser, 
minor  variation  53);  type  collection,  Douglas  (NY,  tracing  and  fragment  from  the  type); 
west  of  Skagit  River,  British  Columbia,  Macoun  769245  (NY,  minor  variation  53,  A. 
michauxiana  Besser). 

lie.  Artemisia  vulgaris  redolens  (Gray). — Stems  erect,  4  to  8  dm.  high,  from  root- 
stocks;  lower  leaves  oblanceolate  or  obovate,  twice  pinnately  dissected;  principal  leaves 
obovate  or  broadly  eUiptic  in  outline,  3  to  5  cm.  long,  nearly  as  wide,  dissected  to  the 
midrib  into  spreading  lobes,  these  commonly  parted  into  linear  spreading  lobes  or  at 
least  toothed,  the  leaves  of  the  inflorescence  simply  parted  or  entire,  all  sparsely  tomen- 
tulose  or  glabrate  above  and  moderately  white-tomentose  beneath,  the  margins  narrowly 
revolute;  inflorescence  an  open  leafy  panicle  with  ascending  branches,  10  to  15  cm.  broad; 
involucre  campanulate,  3  to  3.5  mm.  high,  3  mm.  broad,  sparingly  silky-tomentose,  15- 
to  20-flowered  (A.  redolens  Gray,  Proc.  Am.  Acad.  21:393,  1886).  Chihuahua,  Durango, 
and  probably  in  other  of  the  States  of  northern  Mexico.  Type  locality,  near  Chihuahua 
City,  on  cool  slopes  under  cUffs.  Collections:  Type  collection,  Pringle  296  (Gr,  NY); 
same  locaUty,  Pringle  1059  (NY,  UC);  barranca  below  Sandia  Station,  Durango, 
Pringle  13535  (Gr,  US). 

11/.  Artemisia  vulgaris  flodmani  (Rydberg). — Stems  erect,  3  to  5  dm.  high,  from 
branched  rootstocks;  lower  leaves  obovate  or  oblanceolate,  deeply  cut  into  spreading 
divisions  which  are  again  toothed  or  lobed ;  principal  leaves  (as  far  as  known)  obovate  in 
outline,  3  to  7  cm.  long,  2  to  4  cm.  wide,  dissected  nearly  to  the  midrib  into  lanceolate 
lobes,  these  mostly  again  cleft,  the  uppermost  leaves  entire  or  simply  cleft,  all  with  a 
persistent  tomentum  on  both  faces,  but  this  denser  and  whiter  beneath,  the  margins 
revolute;  inflorescence  a  rather  dense  leafy  panicle  1  to  2  cm.  broad  (broader  in  one  of  the 
type  specimens,  but  this  due  to  injury  to  the  central  axis);  involucre  campanulate,  about 
3  mm.  high  and  broad,  gray  with  a  loose  persistent  tomentum,  about  20-  to  30-flowered. 
{A.  flodmani  Rydberg,  N.  Am.  Fl.  34:276,  1916.)  Mountains  of  Montana,  Idaho,  and 
western  Wyoming,  doubtful  specimens  also  from  northeastern  Utah  and  eastern  Oregon ; 
rare.  Type  locaUty,  Little  Belt  Mountains,  Montana,  9  miles  east  of  Barker.  Collec- 
tions: Type  collection,  Flodman  883  (NY) ;  Coal  Creek,  Teton  Mountains,  Wyoming,  near 
timber-line.  Hall  II444  and  II445  (UC);  same,  but  at  2,250  m.  altitude,  in  the  lodgepole 
forest,  Hall  11438  (UC) ;  Twilight  Gulch,  Owyhee  County,  Idaho,  Macbride  486  (UC). 


76  GENUS   ARTEMISIA. 

llg.  Artemisia  vulgaris  heterophylla  (Nuttall). — Stems  3  to  15  or  even  20  dm. 
high,  from  horizontal  rootstocks,  often  in  thicket  formation  on  good  soil,  or  scattered; 
lower  leaves  oblanceolate  or  obovate,  coarsely  few-lobed;  principal  leaves  oblanceolate 
or  broadly  elliptic  in  outline,  often  somewhat  spatulate,  long-acute,  7  to  15  cm.  long, 
1.5  to  5  or  10  cm.  wide,  saliently  cut-toothedor  cleft,  the  lobes  few,  lanceolate,  acute,  and 
forward-pointing,  or  sometimes  the  leaves  mostly  entire  (variations  illustrated  on  p.  41), 
and  those  of  the  inflorescence  usually  so  and  much  reduced,  all  sparsely  tomentulose  and 
green  above,  densely  white-tomentose  beneath,  the  margins  obscurely  revolute  or  plane; 
inflorescence  an  elongated  pyramidal  panicle,  2  to  8  cm.  broad;  involucre  campanulate, 
3  to  4  mm.  high,  2.5  to  3.5  mm.  broad,  gray-tomentose,  15-  to  30-flowered  {A.  heterophylla 
Nuttall,  Trans.  Am.  Phil.  Soc.  II,  400,  1841).  Saskatchewan  and  Idaho  to  the  Pacific 
Coast  from  British  Columbia  to  Lower  California;  the  most  abundant  subspecies  in 
Oregon  and  Cahfornia.  Type  locality,  "Rocky  Mountains  by  streams."  Collections: 
Type  collection,  Nuttall  (Or);  near  Red  Lodge,  Montana,  Rose  664  (US);  Lake  Pend 
d'Oreille,  northern  Idaho,  Sandberg  822  (US);  Tamarack,  Washington  County,  Idaho, 
Clark  227  (UC) ;  West  Klickitat  County,  Washington,  Suksdorf  871  (UC) ;  Wawawai, 
Snake  River  Canon,  Washington,  Pi-per  6466  (US,  type  of  A.  atomifera  Piper,  minor 
variation  4);  Grants  Pass,  Oregon,  July  14,  1887,  Howell  (UC);  damp  land  near  Yreka, 
northern  California,  Butler  1798  (UC);  valley  of  the  Van  Duzen  River,  Cahfornia, 
Tracy  3976  (UC) ;  Chico,  California,  Heller  11135  (Or,  NY,  UC,  US) ;  Red  Clover  Valley, 
northern  Sierra  Nevada  Mountains,  California,  Heller  and  Kennedy  8876  (UC,  NY, 
US,  a  form  common  in  the  mountains,  with  thin  and  rather  narrow  leaves;  intermediate 
to  subspecies  ludoviciana) ;  Pacific  Grove,  Monterey  County,  California,  Heller  7195 
(DS,  UC) ;  Clear  Creek  Canon,  western  Nevada,  Baker  1458  (Gr,  NY,  UC) ;  near  Mesmer, 
Los  Angeles  County,  Cahfornia,  Ahrams  2955  (DS,  Gr,  NY,  UC,  US);  Avalon,  Santa 
Catalina  Island,  September  1897,  Trask  (US). 

\\h.  Artemisia  vulgaris  litoralis  (Suksdorf). — Stems  6  to  15  dm.  high  (or  more), 
from  large  sometimes  suffrutescent  rootstocks;  lower  leaves  oblanceolate  or  obovate, 
coarsely  few-toothed  or  few-lobed ;  principal  leaves  broadly  lanceolate  or  broadly  elliptic 
in  outline,  sometimes  nearly  oblanceolate,  gradually  acute,  7  to  15  cm.  long,  1.5  to  3  cm. 
wide,  with  a  few  prominent  teeth  or  short  lobes,  these  lanceolate  acute  and  forward- 
pointing,  some  of  the  leaves  commonly  entire,  especially  the  narrow  elongated  ones  of 
the  inflorescence,  all  very  sparsely  tomentulose  and  green  above,  densely  white-tomentose 
beneath,  the  margins  very  narrowly  revolute  or  plane;  inflorescence  an  elongated  leafy 
panicle,  3  to  9  cm.  broad;  involucre  ovoid,  3  to  4  mm.  high,  2  to  2.5  mm.  broad,  obscurely 
tomentulose  or  apparently  glabrous,  yellowish-green  and  shining,  8-  to  12-flowered. 
{A.  vulgaris  var.  litoralis  Suksdorf,  Deut.  Bot.  Monats.  18:98,  1900.)  Along  the 
Pacific  Coast  from  British  Columbia  to  Cape  Mendocino,  California;  common  on  the 
bluffs  of  Puget  Sound.  Type  locality,  stony  sea-beaches  near  Fairhayen,  Washington. 
Collections :  Chilliwack  Valley,  British  Columbia,  Macoun  26352  (Gr) ;  Vancouver  Island, 
June  28,  1887,  Macoun  (US) ;  Chuckanut  Bay,  Washington,  July  5,  1890,  Suksdorf  980 
(NY,  UC,  US,  apparently  the  type  collection);  Fairhaven,  Washington,  Piper  2808 
(Gr) ;  east  of  Scenic,  Washington,  Otis  804  (SF) ;  Quiniault  Valley,  Washington,  Conard 
260  (Gr);  mouth  of  the  Umpqua  River,  Oregon,  June,  1887,  Howell  (NY,  UC,  US); 
Shelter  Cove,  Humboldt  County,  California,  Bolander  6482  (Gr) ;  near  Scotia,  Humboldt 
County,  California,  Davy  and  Blasdale  5544  (UC);  Cape  Mendocino,  California,  Tracy 
4973  (UC). 

lit.  Artemisia  vulgaris  ludoviciana  (Nuttall). — Stems  erect,  3  to  10  dm.  high, 
often  crowded  on  the  rootstocks  or  scattered;  lower  leaves  oblanceolate,  lobed  or  entire; 
principal  leaves  linear  or  oblanceolate  in  outhne,  3  to  9  cm.  long,  0.5  to  2  cm.  wide, 


A.    VULGARIS.  77 

mostly  cleft  into  few  divergent  linear-lanceolate  acute  lobes,  sometimes  mostly  entire 
or  only  dentate,  the  uppermost  entire,  all  gray  and  loosely  floccose  or  green  and  nearly 
glabrous  above,  white-tomentose  beneath  (see  note  under  citation  of  type  specimen); 
inflorescence  an  elongated  narrow  compact  panicle,  1.5  to  3  cm.  broad  or  sometimes 
leafy,  more  branched,  and  then  up  to  10  cm.  broad;  involucre  campanulate,  about  3  mm. 
high,  2.5  to  3  mm.  broad,  more  or  less  tomentose  (green  and  nearly  glabrous  in  form  known 
as  A.  potens),  12-  to  20-flowered.  (A.  ludoviciana  Nuttall,  Genera  2:143,  1818.)  Abun- 
dant and  widely  distributed  in  western  North  America:  Montana,  and  perhaps  farther 
north,  to  Wisconsin,  Kansas,  Texas,  Chihuahua,  California,  Washington,  and  Idaho; 
introduced  in  New  England  (Collins,  Rhodora  1 :47,  1899;  Fernald  and  Wiegand,  Rhodora 
12:144,  1910).  Type  locality,  on  the  banks  of  the  Mississippi  River  near  St.  Louis. 
Collections  (mostly  with  leaves  much  greener  above  than  in  the  type) :  Wild  Horse 
Island,  Montana,  Butler  469  (NY);  Fort  Howard,  Wisconsin,  September  15,  1878, 
Schuette  (UC,  intermediate  to  subspecies  gnaphalodes) ;  Woods  Creek,  Wyoming,  Nelson 
8046  (UC);  Mclntyre  Creek,  Larimer  County,  Colorado,  Oslerhout  2242  (Osterhout 
Hb,  R,  NY,  type  collection  of  A.  silvicola  Osterhout,  minor  variation  76) ;  Idaho  Springs, 
Colorado,  Shear  4617  (NY,  type  of  A.  cuneata  Rydberg,  minor  variation  10) ;  near  Ouray, 
Colorado,  Underwood  and  Selby  74  (NY,  type  of  A.  underwoodi  Rydberg,  minor  variation 
88) ;  Riley  County,  Kansas,  Norton  300  (NY) ;  Courtney,  Missouri,  Bush  6509  (Or,  NY) ; 
type  collection,  "St.  Louis,"  Nuttall  (Phila.,  leaves  more  tomentose  above  than  in  most 
specimens  here  cited,  but  the  tomentum  much  less  dense  than  on  the  under  surface 
where  it  is  closely  felted  and  white) ;  Ottawa,  Oklahoma,  Stevens  2500  (Gr) ;  Weatherford, 
Texas,  Tracy  8135  (NY);  near  Colonia  Garcia,  Chihuahua,  Townsend  and  Barber  326 
(NY);  Cananea,  Sonora,  Donnelley  44  (UC);  near  Pecos,  San  Miguel  County,  New 
Mexico,  Standley  5118  (NY);  Fort  Lowell,  Arizona,  Thornier  50  (UC,  NY);  Bear  Valley, 
San  Bernardino  Mountains,  California,  Ahrams  2823  (Gr,  NY);  trail  to  Mount  Whitney, 
California,  Culbertson  434I  (NY,  minor  variation  62,  A.  potens  Nelson);  Charleston 
Mountains,  Nevada,  Heller  11086  (NY,  same  variation);  Marysvale,  Utah,  Jones  5846 
(UC,  NY);  Columbia  River,  Washington,  Suksdorf  1610  (UC). 

llj.  Artemisia  vulgaris  gnaphalodes  (Nuttall). — Stems  erect,  3  to  10  dm.  high, 
from  creeping  rootstocks;  lower  leaves  oblanceolate  or  somewhat  cuneate  to  Unear, 
entire  or  often  with  a  few  teeth  or  even  pinnately  cleft  into  lanceolate  lobes;  principal 
leaves  linear  to  broadly  elliptic  in  outline,  3  to  10  cm.  long,  0.5  to  3  cm.  wide,  mostly 
entire  in  the  typical  form  but  varying  to  dentate,  cleft,  or  even  divided  into  several 
linear-lanceolate  acute  ascending  lobes,  those  of  the  inflorescence  chiefly  entire  and 
narrow,  all  leaves  densely  permanently  and  equally  white-tomentose  on  both  sides, 
the  margins  essentially  plane  (connects  with  subspecies  longifolia  through  forms  with 
leaves  entire  and  broad  but  glabrate  and  through  others  with  leaves  narrow  but  per- 
manently tomentose,  while  the  form  with  prominent  short  and  broad  leaf -lobes  is  A. 
brittoni  Rydberg,  minor  variation  6);  inflorescence  an  elongated  panicle,  dense,  2  to  5 
cm.  broad;  involucre  campanulate,  3  to  3.5  mm.  high,  about  3  mm.  broad,  densely  tomen- 
tose, 15-  to  30-flowered  (lower  counts  probably  due  to  the  falling  out  of  some  of  the 
flowers).  (A.  gnaphalodes  Nuttall,  Genera  2:143,  1818.)  Ontario  and  Michigan  to 
Missouri,  Texas,  Coahuila,  California,  British  Columbia,  and  Saskatchewan;  introduced 
in  Pennsylvania  and  along  the  Atlantic  Coast  from  Quebec  to  Massachusetts.  Type 
locality,  dry  savannahs  about  Green  Bay,  Lake  Michigan.  Collections:  Newbury, 
Massachusetts,  introduced,  August  7,  1899,  Williams  (Gr);  Point  Edward,  Lake  Huron, 
Ontario,  Macoun  2635  (NY,  US);  Lake  Mendota,  Madison,  Wisconsin,  August  24,  1893, 
Sudworth  (NY,  US);  Oregon,  Ogle  County,  Illinois,  September  2,  1886,  Waite  (US); 
Moscow,  Iowa,  Somes  3707  (US);  near  Thedford,  central  Nebraska,  Rydberg  1725  (Gr, 
US);  Black  Hills  Forest,  South  Dakota,  Murdoch  4305  (Gr);  Centennial,  Wyoming, 


78 


GENUS   ARTEMISIA. 


Goodding  2119  (Gr,  NY,  UC,  US);  Red  Desert  near  Creston,  Wyoming,  Nelson  U^6 
(R,  type  of  A.  rhizomata  pabularis  Nelson,  minor  variation  73);  Laramie,  Wyoming, 
Nelson  6896  (UC,  minor  variation  72,  A.  rhizomata  Nelson) ;  Golden,  Colorado,  September 
6,  1919,  Hall  (CI,  includes  several  forms  of  leaves,  some  representing  A.  brittoni  Rydberg, 
see  fig.  12,  p.  95);  Gunnison,  Colorado,  Baker  573  (UC,  Gr,  NY,  minor  variation  65, 
A.  pudica  Rydberg);  McPherson,  Kansas,  September  5,  1890,  Kellerman  (US) ;  Courtney, 
Missouri  (introduced?),  Bush  5858  (Gr,  NY,  US);  Woods  County,  Oklahoma,  Stevens 
2869  (Gr);  Colorado,  Texas,  Tracy  81 41  (Gr,  NY,  type  collection  of  A.  texana  Rydberg, 
minor  variation  82) ;  vicinity  of  Saltillo,  Coahuila,  Palmer  286  (Gr,  NY,  UC,  US,  minor 


Fio.  8. 

Portions  of  the  type  specimens  of  Arte- 

misia  vulgaris  ludoviciana  and  A.  v.  gnapho' 
lodes:  a  to  e,  from  tracings  of  the  type  of 
ludoviciana;  f,  from  a  tracing  of  the  type  of 
gnaphalodes;  both  types  in  the  Herbarium  of 
of  the  Academy  of  Natural  Sciences  of  Phila- 
delphia. The  foliage  of  a  to  e  is  slightly 
greener  above  than  below,  that  of  /  is  equally 
white-tomentose  on  both  faces.     All  X  1. 


variation  6,  A.  brittoni  Rydberg,  so  determined  by  Rydberg);  Dona  Ana  County,  New 
Mexico,  Wooton  504  (NY,  US,  type  collection  of  A.  albula  Wooton,  minor  variation  1); 
Humboldt  County,  Nevada,  Torrey  249  (Gr);  Tantillas  Canon,  San  Diego  County, 
California,  1875,  Palmer  (Gr,  minor  variation  1,  A.  albula  Wooton);  San  Jacinto  Canon, 
southern  California,  Johnston  1847  (NY);  Davis  Creek,  northeastern  California,  July, 
1895,  Austin  (UC);  Spokane,  Washington,  Sandberg  900  (NY,  minor  variation  67, 
A.  purshiana  Besser);  Columbia  River,  Washington,  Scouler  234  (NY,  type  of  A.  obtusa 
Rydberg,  minor  variation  58);  Nampa,  Idaho,  Nelson  and  Macbride  1081  (DS,  Gr,  NY, 
UC,  minor  variation  67,  A.  purshiana  Besser);  Beavermouth,  British  Columbia,  Shaw 
1153  (Gr);  Bozeman,  Montana,  Blankinship  255  (US);  Indian  Head,  Assiniboia,  Macoun 
10984  (US);  Sarcee  Reserve,  Alberta,  Goddard  492  (UC). 

IIA;.  Artemisia  vulgaris  longifolia  (Nuttall). — Stems  erect,  3  to  10  dm.  high,  often 
clustered  on  a  strong  woody  rootstock;  lower  leaves  narrowly  lanceolate  or  slightly  oblan- 
ceolate,  sometimes  with  a  few  prominent  teeth  or  lobes;  principal  leaves  linear  or  very 
narrowly  lanceolate,  commonly  caudate-attenuate,  5  to  15  cm.  long,  0.2  to  0.5  cm.  wide, 
entire  (apparently  a  form  with  slender  lobes  grows  on  gumbo  soil,  see  minor  variation  18, 
A.  falcata  Rydberg),  those  of  the  inflorescence  linear-attenuate  and  much  reduced,  all 
leaves  loosely  floccose  and  glabrate  above  (in  the  typical  form),  white-tomentose  beneath, 
the  margins  strongly  revolute;  inflorescence  a  strict  panicle,  1  to  8  cm.  broad;  involucre 


A.   VULGARIS. 


79 


campanulate,  about  4  mm.  high,  3  to  4  mm.  broad,  densely  tomentose,  sometimes  a 
little  glabrate,  20-  to  30-flowered.  (A.  longifolia  Nuttall,  Genera  2:142,  1818.)  South- 
central  Canada  to  Nebraska,  Colorado,  Wyoming,  and  Montana;  also  west  to  Oregon 
and  Washington,  according  to  North  American  Flora.  Type  locality,  rocky  situations 
on  the  banks  of  the  Missouri  River.  Collections:  Saskatchewan,  1858,  Bourgeau  (Gr, 
a  form  with  leaves  green  above  and  a  very  open  inflorescence);  vicinity  of  Rosedale, 
Alberta,  Moodie  1097  (DS,  Gr,  SF,  NY);  Fort  Pierre,  Nebraska,  July,  1853,  Hayden 
Survey  (NY) ;  Lake  De  Smet,  Wyoming,  Nelson  8545  (UC,  NY,  US) ;  Washington  County, 
South  Dakota,  August,  1886,  Hatcher  (UC);  plains,  Colgate,  near  Glendive,  eastern 
Montana,  Sandberg  1011,  1014  (Gr,  NY,  SF,  US). 

111.  Artemisia  vulgaris  serrata  (Nuttall). — Stems  strictly  erect,  10  to  30  dm. 
high,  from  rootstocks;  lower  leaves  lanceolate,  closely  and  rather  evenly  serrate  (for 
deviations  see  fig.  13);  principal  leaves  lanceolate  or  linear-lanceolate,  acuminate,  7  to 
15  cm.  long,  1  to  2.5  cm.  wide,  serrate  like  the  lower,  only  the  very  tip  and  about  1  cm. 
near  the  base  entire,  the  teeth  2  mm.  or  less  long,  those  of  the  inflorescence  gradually 
reduced,  narrower  and  mostly  entire,  all  of  the  leaves  green  and  glabrous  above,  white- 
tomentose  beneath,  the  margins  sometimes  obscurely  revolute;  inflorescence  a  leafy 
panicle,  5  to  15  cm.  broad;  involucre  narrowly  campanulate,  2.7  to  3  mm.  high,  about 
2  mm.  broad,  more  or  less  floccose,  12-  to  20-flowered.  (A.  serrata  Nuttall,  Genera 
2:142,  1818.)  Restricted  to  the  central  and  northern  portions  of  the  Mississippi  Valley, 
except  as  naturalized  further  east,  as  in  northern  New  York;  Wisconsin  to  northern 
Illinois,  Kansas  (?),  Iowa,  North  Dakota,  and  Minnesota.  Type  locality,  near  the 
Prairie  du  Chien,  on  the  banks  of  the  Mississippi  River.  Collections:  Upper  Louisiana, 
Nuttall  (Phila,  one  of  the  type  collections);  Taylors  Falls,  Minnesota,  August,  1892, 
Taylor  (DS,  NY,  UC,  US);  Glenwood,  Minnesota,  August,  1891,  Taylor  (UC,  typical 
in  every  detail  except  that  the  leaves  are  entire);  Dane  County,  Wisconsin,  Wibbe 
(US) ;  prairies  of  Winnebago  County,  Illinois,  August,  1859,  Bebb  (Gr);  Fayette  County, 
Iowa,  Fink  404  (US). 

11m.  Artemisia  vulgaris  lindleyana  (Besser). — Stems  erect,  1.5  to  4  dm.  high, 
usually  several  from  a  woody  rootstock;  lower  leaves  oblanceolate,  toothed  or  lobed; 
principal  leaves  linear  or  oblanceolate  in  outline,  2  to  5  cm.  long,  0.4  to  1.5  cm.  wide, 
sharply  toothed  or  cleft  into  short  divergent  lanceolate  lobes,  the  upper  ones  mostly 
entire,  loosely  floccose  or  green  and  glabrate  above,  white-tomentose  beneath;  inflores- 
cence a  short  and  narrow  raceme-like  panicle  (sometimes  completely  racemose,  sometimes 
with  a  few  erect  racemiform  branches),  0.5  to  2  cm.  broad;  involucre  campanulate,  3  to 
4  mm.  high,  2  to  3  mm.  broad,  tomentose,  but  the  tomentum  often  thin  and  partly 
deciduous;  heads  18-  to  30-flowered.  (A.  lindleyana  Besser,  in  Hooker,  Fl.  Bor.  Am. 
1:322,  1833.)  West  of  the  Rocky  Mountains  from  Montana  to  Utah,  Arizona,  eastern 
CaUfornia,  Washington,  and  Idaho.  Type  locality,  northwest  coast  of  America.  Col- 
lections: Type  collections,  northwest  America,  Douglas  (Gr,  ex-herb.  Lindley,  fragments 
of  legitima,  brevifolia,  subdentata,  coronopus,  leaves  entire  to  once-cleft,  minor  variations 
38  to  41);  Lewis  River,  Rocky  Mountains,  Nuttall  (Gr,  Phila,  type  of  A.  pumila  Nuttall, 
minor  variation  66);  head  of  dry  wash,  Abajo  Mountains,  southeastern  Utah,  Rydberg 
and  Garrett  9615  (NY);  Holbrook,  Arizona,  October  9,  1897,  Zuck  (NY,  inflorescence 
racemose-spicate  but  otherwise  like  minor  variation  76,  A.  silvicola  Osterhout);  Sequoia 
National  Park,  southern  Sierra  Nevada,  CaUfornia,  Davidson  2057  (UC);  Fish  Hook 
Ferry,  eastern  Oregon,  Leiberg  935  (NY,  type  of  A.  leibergi  Rydberg,  minor  variation  35) ; 
banks  of  the  Columbia  River,  Washington,  Suksdorf  1611  (UC,  Gr,  NY);  Clarks  Fork 
Valley,  Idaho,  Leiberg  1567  (UC);  near  Thompson  Mountain,  northern  Idaho,  Leiberg 
1610  (NY,  inflorescence  inclined  to  branch). 


80  GENUS   AHTEMISIA. 

lln.  Artemisia  vulgaris  mexicana  (Willdenow). — Stems  erect,  3  to  8  dm.  high, 
from  slender  herbaceous  rootstocks,  more  densely  leafy  than  in  most  other  varieties; 
lower  leaves  narrowly  oblanceolate,  cleft  into  several  very  slender  lobes;  principal  leaves 
linear  or  the  outline  often  oblanceolate  because  of  the  divergent  lobes,  3  to  10  cm.  long, 
only  0.2  to  0.4  cm.  wide  when  entire  but  up  to  5  cm.  wide  across  the  spreading  lobes 
when  these  are  present,  typically  cleft  nearly  to  the  midrib  into  elongated  linear  acute 
lobes  2  to  4  mm.  wide,  those  of  the  inflorescence  chiefly  entire,  all  leaves  green  and  lightly 
tomentose  or  glabrate  above,  densely  white-tomentose  beneath,  the  margins  narrowly 
revolute;  inflorescence  a  leafy  panicle,  3  to  8  cm.  broad;  involucre  campanulate,  2.5  to  3 
mm.  high,  about  3  mm.  broad,  or  4  mm.  high  and  broad  in  form  known  as  A.  ghiesbreghti 
Rydberg,  gray-tomentose,  perhaps  sometimes  only  sparingly  so,  15-  to  30-flowered. 
{A.  mexicana  Willdenow;  Sprengel,  Syst.  3:490,  1826.)  Dry  plains  from  Missouri, 
southern  Colorado,  and  Texas  to  New  Mexico  and  probably  Arizona,  thence  south 
and  apparently  common  to  San  Luis  Potosi,  Durango,  Jalisco,  Vera  Cruz,  Yucatan 
(according  to  Millspaugh,  Field  Mus.  Nat.  Hist.  Bot.  1:323,  1896),  Chiapas,  and  probably 
into  Guatemala.  Type  locality,  Mexico.  Collections:  Greenwood,  Missouri,  Bush  1^12 
(Gr,  NY,  US,  minor  variation  36,  A.  lindheimeriana  Scheele);  Wichita,  Kansas,  Poole 
1300  (US,  same  variation);  foot  of  Spanish  Peaks,  Colorado,  September  3,  1873,  Greene 
(Gr) ;  Naturita,  southwestern  Colorado,  Payson  590  (Gr) ;  White  Mountains,  New  Mexico, 
Wooton  3U  (Gr,  UC,  US);  Black  Range,  New  Mexico,  Metcalfe  1248  (NY,  type  of 
A.  neomexicana  Greene,  minor  variation  57);  Weatherford,  Texas,  Tracy  8135  (Gr); 
near  Chihuahua  City,  Chihuahua,  Pringle  290  (NY,  type  of  A.  revoluta  Rydberg); 
near  San  Julian,  Chihuahua,  Nelson  4939  (Gr,  US) ;  Sierra  des  Parras,  Coahuila,  Purpus 
4659  (UC,  condensed  form  with  short  leaves  and  narrow  inflorescence;  perhaps  nearer 
subspecies  ludoinciana) ;  near  Durango,  Palmer  907  (Gr,  UC,  US);  Alvarez,  San  Luis 
Potosi,  Palmer  59  (Gr,  UC,  US);  Tula,  Hidalgo,  Pringle  9848  (Gr,  NY,  US);  slopes  of 
barranca  of  Guadalajara,  1,380  m.,  Jalisco,  Pringle  8765  (Gr,  UC,  US);  Eslava,  Federal 
District,  Mexico,  Pringle  11820  (Gr,  US,  heads  exceptionally  large,  minor  variation  21, 
A.  ghiesbreghti  Rydberg);  Esperanza,  Puebla,  Arsene  2113  (US);  Orizaba,  Mueller  1868 
(NY,  type  of  A.  muelleri  Rydberg,  minor  variation  55). 

llo.  Artemisia  vulgaris  wrighti  (Gray). — Stems  erect,  3  to  6  dm.  high,  from  short 
creeping  rootstocks;  lower  leaves  of  sterile  shoots  elliptic  or  lanceolate,  entire,  densely 
white-tomentose  on  both  sides;  lower  leaves  of  flowering  stems  usually  cleft  or  divided 
into  hnear-fihform  lobes;  principal  leaves  oblanceolate  in  outline,  1  to  5  cm.  long,  0.5  to 
1  cm.  wide  including  spread  of  the  lobes,  some  of  upper  ones  entire  but  mostly  cleft  or 
divided  into  linear-filiform  acute  lobes,  these  0.5  to  1  mm.  wide,  those  of  the  inflorescence 
reduced  but  similar,  all  leaves  white-tomentose  on  both  sides  (minor  variation  8,  A. 
carruthi  Wood),  or  greener  and  glabrate  above  (typical),  those  of  the  inflorescence  reduced 
but  similar,  the  margins  closely  revolute;  inflorescence  a  close  panicle,  1  to  3  cm.  broad, 
or  the  individual  panicles  so  arranged  as  to  form  a  more  compound  and  much  broader 
inflorescence,  or  sometimes  reduced  to  a  nearly  simple  raceme;  involucre  campanulate, 
3  to  3.3  mm.  high,  2  to  2.5  mm.  broad  (larger  in  forms  known  as  A.  pringlei  and  A. 
prescottiana) ,  pale,  tomentulose,  10-  to  35-flowered.  {A.  wrighti  Gray,  Proc.  Am.  Acad. 
19:48,  1883.)  Kansas  to  western  Texas,  Chihuahua,  Arizona,  Utah,  and  central  Colo- 
rado; an  aberrant  type  reported  from  the  Columbia  River  (minor  variation  63,  A.  pres- 
cottiana Besser) ;  introduced  into  Missouri  and  Rhode  Island.  Type  locaUty,  Santa 
Rita  del  Cobre,  New  Nexico,  according  to  Rydberg.  Collections  (many  are  the  form 
known  as  A.  carruthi  Wood,  i.  e.,  minor  variation  8) ;  Pawtucket,  Rhode  Island,  on  wastes, 
October,  1898,  McCudden  (Gr);  Lane  County,  Kansas,  Hitchcock  302  (Gr,  NY,  US, 
apparently  the  type  collection  of  A.  kansana  Britton,  minor  variation  33);  Amarillo, 


A.    VULGARIS.  81 

Texas,  Ball  II4I  (US);  near  Dulce,  New  Mexico,  Standley  8270  (US);  type  collection, 
Wright  1279  (NY);  plains  near  the  City  of  Chihuahua,  Chihuahua,  Pringle  625  (Gr, 
type  of  A.  pringlei  Greenman,  minor  variation  64);  Chiricahua  Mountains,  Arizona, 
Blumer  1794  (DS,  Gr,  NY,  US);  Flagstaff,  Arizona,  September  2,  1889,  Sheldon  (UC); 
along  San  Juan  River,  southeastern  Utah,  Rydberg  and  Garrett  10006  (NY,  UC) ;  Marshall 
Pass,  Colorado,  Baker  879  (NY,  UC,  US);  Black  Canon,  Colorado,  Baker  698  (Gr,  UC, 
US,  minor  variation  5,  A.  hakeri  Greene). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Artemisia  albula  Wooton,  Contr.  U.  S.  Nat.  Herb.  16:193,  1913. — A  form  of  arid  situations  in  the 
southern  Rocky  Mountain  States  and  northern  Mexico,  here  included  under  A.  vulgaris  gnaphalodes,  but  with 
distinctive  habit,  very  narrow  leaves,  widely  branched  inflorescence,  and  exceptionally  small  heads,  the  in- 
volucres 3  mm.  high.  The  following  collections  belong  here :  Organ  Mountains,  Dona  Ana  County,  New  Mexico, 
at  1,400  meters  altitude,  Wooton  504  (NY,  US,  type  collection);  near  Fort  Huachuca,  Arizona,  Lcmmon  27S3^ 
(Gr);  Limestone  Hill,  Cochise  County,  Arizona,  Eggleslon  10966  (Gr);  Tantillas  Caiion,  San  Diego  County, 
California,  1875,  Palmer  (Gr);  Sierra  en  Media,  Chihuahua,  Nelson  6488  (Gr). 

2.  A.  ARACHNOIDEA  Sheldon,  Bull.  Torr.  Club,  30:310,  1903.^A  variation  intermediate  between  A.  vulgaris 
tilesi  and  A.  v.  heterophylla,  with  heads  about  4  mm.  high  and  with  25  to  35  flowers.  Originally  distinguished 
from  tilesi  by  the  "subsecund  loose  inflorescence  and  peculiar  involucral  bracts."  The  involucre  is  subtended 
by  a  few  minute  bracts,  as  is  common  in  A.  vulgaris,  and  is  arachnoid-pubescent  as  occurs  also  in  tilesi.  The 
lower  leaves  are  mostly  wanting  in  the  specimens  distributed  under  the  type  number,  but  the  remaining  ones 
show  deep  lobes  suggestive  of  both  tilesi  and  heterophylla.  Type  locality,  sandy  banks  of  the  Columbia  River, 
1  mile  west  of  Vancouver,  Washington. 

3.  A.  ARGOPHYLLA  Rydberg,  N.  Am.  Fl.  34:274,  1916.— Intermediate  between  A.  vulgaris  gnaphalodes 
and  A.  v.  candicans.  The  type  specimen  is  like  the  former,  but  very  robust  and  with  large  heads,  the  involucres 
fully  4  mm.  high.  Type  locality,  near  Long's  Peak,  Colorado.  Specimens  referred  here  come  also  from  as 
far  west  as  northern  California  and  eastern  Washington. 

4.  A.  ATomFERA  Piper,  Contr.  U.  S.  Nat.  Herb.  11 :588, 1906.— A  form  or  race  of  A.  vulgaris  heterophylla, 
but  the  upper  surface  of  the  leaves,  as  also  the  involucres,  speckled  with  numerous  white  resinous  atoms.  A 
series  of  specimens  gathered  with  the  type  exhibit  a  wide  variation  in  the  leaves  from  entire  to  pinnately  divided. 
Type  locality,  Wawawai,  Washington. 

5.  A.  BAKERi  Greene,  PI.  Baker  3:31,  1901.— Perhaps  best  referred  to  A.  vulgaris  wrighti  because  of  the  very 
narrow  leaf -lobes,  none  of  which  reach  2  mm.  in  breadth,  but  intermediate  to  subspecies  ludoviciana  through 
its  wider-leaved  forms.  The  foHage  is  green  and  glabrate  above,  greener  than  in  typical  A.  wrighti,  from  which 
it  also  differs  in  the  mostly  nodding  and  slightly  larger  heads.  The  position  assumed  by  the  heads  is  not  con- 
sidered important.  Plants  with  gray  foliage  and  all  other  characters  of  the  carruthi  form  of  subspecies  unighti 
sometimes  have  heads  as  uniformly  nodding  as  in  hakeri,  for  example,  Pagosa  Springs,  southern  Colorado, 
Baker  749  (UC).  The  type  was  collected  by  Greene  in  the  canon  of  the  Gunnison,  near  Cimarron,  Colorado. 
This  has  not  been  seen,  but  the  above  notes  are  based  upon  other  specimens  cited  by  Greene,  namely,  Black 
Canon,  Gunnison  Watershed,  Colorado,  Baker  698  (Gr,  UC,  US). 

6.  A.  BRiTTONi  Rydberg,  Bull.  Torr.  Club  32:129,  1905.— A  form  of  A.  vulgaris  gnaphalodes  in  which  the 
heavily  tomentose  leaves  are  parted  into  3  to  5  short  and  rather  broad  divergent  lobes.  This  is  one  of  the 
extreme  types  of  lobing  and  therefore  appears  very  distinct  when  compared  with  normal  gnaphalodes.  A 
gradation  in  the  character  as  it  occurs  at  Golden,  Colorado,  the  type  locality,  is  shown  m  figure  12,  page  95. 
(See  also  under  A.  diversifolia  of  this  list.) 

7.  A.  CANDICANS  Rydberg,  Bull.  Torr.  Club  24:296,  1897.— A.  vulgaris  candicans. 

8.  A.  CARRUTHI  Wood,  in  Carruth,  Trans.  Kans.  Acad.  Sci.  5:51,  1877.— The  oldest  name  for  .4.  vulgaris 
wrighti,  but  not  well  estabUshed.  A .  carruthi  is  the  state  or  form  in  which  the  leaves  are  about  equally  tomentose 
on  the  two  sides.  In  habit,  width  of  leaf  and  lobes,  inflorescence,  and  size  of  heads  and  flowers  the  two  are 
exactly  alike.  The  difference  in  the  amount  of  tomentum  on  the  upper  surface  of  the  leaves  is  not  so  signifi- 
cant as  the  difference  between  certain  other  pairs  of  forms  here  given  subspecific  rank,  for  example,  gnaphalodes 
and  ludoviciana,  not  only  because  the  leaves  are  narrower  and  the  difference  therefore  less  noticeable,  but  also 
because  of  the  presence  of  all  degrees  of  variation  in  plants  growing  very  near  each  other.  This  intergradation 
has  been  noted  at  a  considerable  number  of  stations,  especially  in  southern  Colorado  and  northern  New  Mexico. 
At  some  places  the  amount  of  tomentum  almost  certainly  depends  upon  ecologic  conditions.  Leaves  which 
are  perfectly  glabrous  on  the  upper  surface  have  not  yet  been  found.  Those  of  sterile  shoots  are  always  densely 
white-tomentose  on  both  surfaces,  entirely  regardless  of  the  amount  of  tomentum  on  the  foliage  of  flowering 
stems.  Thus,  there  is  often  an  abrupt  transition  from  the  white  foliage  on  the  short  innovations  clustered 
about  the  base  of  the  plant  to  the  gray  or  greenish  foliage  of  the  middle  and  upper  portions.     It  should  be  noted 


82  GENUS   AKTEMISIA. 

that  when  Gray  proposed  his  A.  wrighti  he  did  not  intend  to  establish  a  species  distinct  from  .4.  carruihi,  the 
earlier  publication  of  which  he  apparently  overlooked.     The  type  of  A.  carruihi  came  from  Kansas. 

9.  A.  coLORADENSis  Ostcrhout,  Bull.  Torr.  Club  27:. 506,  1900.— .4.  vulgaris  wrighti.  The  leaf-segments 
are  unusually  wide  and  revolute-margined.  If  flattened  out  they  would  be  about  3  mm.  wide,  thus  much 
resembling  tho.se  of  some  forms  of  subspecies  Ittdoviciana,  although  more  densely  gray-toraentose  on  the  upper 
surface.  Grows  in  dry,  rocky  places,  which  suggests  that  it  may  be  only  a  xerophytic  ecad  of  the  cut-leaved 
form  of  ludoviciana  or  of  gnaphalodes.     Type  locaUty,  near  Dale  Creek,  Larimer  County,  Colorado. 

10.  A.  CUNE.\T.\  Rydberg,  N.  Am.  Fl.  34:269,  1916. — A  striking  foliage-form  of  A.  vulgaris  ludoviciana. 
The  principal  leaves  are  cuneate-obovate,  2  to  4  cm.  long,  about  1  cm.  wide,  and  with  a  few  salient  teeth  around 
the  wide  summit.  Type  locality,  Idaho  Springs,  Colorado.  Rare,  but  known  from  as  far  west  as  Fishhook 
Ferry,  Franklin  County,  Oregon,  Leiberg  937  (Gr). 

11.  A.  CUNEIFOLIA  Scheele,  Linnaea,  22:162,  1S49.— Not  A.  cuneifolia  De  CandoUe,  1837.  The  types  not 
seen.  Apparently  a  tall,  very  erect,  and  rigid  small-headed  form  of  A.  vulgaris  mexicana.  Type  locality, 
high  places  on  the  prairie  near  New  Braunfels,  Texas. 

12.  A.  DISCOLOR  Douglas,  in  Hooker,  Fl.  Bor.  Am.  1:322,  as  synonym,  1833;  Besser,  Bull.  Soc.  Nat.  Mosc. 
9:46,  1836.— A.  vulgaris  discolor. 

13.  A.  DISCOLOR  iNCOMPTA  Gray,  Syn.  Fl.  P:373,  1884. — Based  upon  A.  incompta  Nuttall,  here  considered 
as  a  trivial  form  of  A.  vulgaris  discolor.     (See  incompta  of  this  list.) 

14.  A.  DivBRSiFOLiA  Rydberg,  Bull.  Torr.  Club  28:20,  1901. — When  restricted  to  the  form  originally 
described,  this  is  the  same  as  .4.  vulgaris  gnaphalodes,  except  that  the  lower  leaves  are  pinnately  cleft  into  3  to  5 
narrowly  lanceolate  acuminate  lobes  which  are  directed  forward.  While  probably  of  gnaphalodes  origin, 
it  may  be  compared  with  ludoviciana,  of  which  it  is  possibly  an  expression  with  both  faces  of  the  leaves  about 
equally  tomentose.  In  the  North  American  Flora  (34:275,  1916)  Rydberg  extends  the  description  to  include 
anything  in  the  way  of  leaves  from  pinnately  cleft  to  "the  upper  or  rarely  aU  entire."  Thus  ".4.  diversifolia" 
becomes  a  convenient  receptacle  for  a  considerable  number  of  leaf-forms,  all  of  which  are  here  assigned  to  sub- 
species gnaphalodes.  Some  of  these  come  very  close  to  the  minor  variation  called  A.  brittoni  Rydberg.  If 
one  is  to  use  the  cut  of  leaf  as  a  specific  character,  as  is  sometimes  done  for  segregates  of  both  gnaphalodes  and 
ludoviciana,  consistency  would  demand  that  it  be  applied  also  in  connection  with  these  forms  conveniently 
assembled  under  diversifolia.  This,  however,  is  an  extreme  to  which  no  one,  apparently,  is  willing  to  go. 
Variations  in  cut  of  leaf  on  plants  from  the  same  area  are  shown  in  the  figures  on  page  95.  Type  locality, 
Priest  River,  Idaho. 

15.  A.  DOMiNGENSis  Urban,  Symb.  Ant.  7:430,  1912. — A  form  of  A.  vulgaris  perhaps  nearest  to  typica. 
The  type  specimen  has  not  been  seen,  but  Doctor  Urban  has  kindly  sent  a  fragment  from  the  Herbarium  of 
Krug  and  Urban  (No.  153d)  which  he  considers  to  be  the  same.  This  was  collected  in  the  mountains  of  Haiti, 
November,  1896.  The  leaves  are  small  and  apparently  without  stipule-lLke  lobes  at  base,  but  otherwise  as 
in  typica,  as  far  as  the  scant  material  indicates.  The  involucre  is  2  mm.  high,  2.6  mm.  broad,  and  of  about 
15  bracts.  The  only  head  dissected  had  28  ray-flowers  and  15  disk-flowers.  The  large  number  of  the  former 
is  remarkable.     The  type  locality  is  near  Constanza,  Santo  Domingo. 

16.  A.  DOUGLASIANA  Bes.ser,in  Hooker,  Fl.  Bor.  Am.  1:323,  1833. — A.  vulgaris  heterophylla.  The  form 
with  nearly  entire  leaves.  Type  locality,  Northwest  America.  (See  discussion  under  A.  hookeriana  of  this  list.) 

17.  A.  ELATiOR  Rydberg,  Mem.  N.  Y  Bot.  Gard.  1:430,  1900. — Based  upon  A.  tilesi  elalior.  (See  under 
this  name  in  the  present  list.) 

18.  A.  FALCATA  Rydberg,  N.  Am.  Fl.  34:271,  1916. — In  every  respect  the  same  as  A.  vtdgaris  longifolia, 
except  that  many  of  the  very  narrow,  elongated  leaves  have  salient  spreading  lobes.  An  almost  exact  match 
for  the  type  except  for  this  lobing  is  found  in  undoubted  longifolia  specimens,  for  example.  Boiler  Rapid, 
Athabasca  River,  Preble  and  Cary  131  (US).  The  foliage  resembles  that  of  mexicana,  but  the  large  heads 
serve  to  distinguish  it  and  the  distribution  is  very  different.  Apparently  confined  to  gumbo  soils  and  known 
only  from  South  Dakota  to  Saskatchewan  within  the  general  area  occupied  by  longifolia.  Type  locality. 
Fort  Pierre,  South  Dakota. 

19.  A.  FLOccosA  Rydberg,  Bull.  Torr.  Club  24:297,  1897.-4.  vulgaris  candicans.  Separated  on  the  basis 
of  the  inflorescence,  the  heads  all  erect  and  on  peduncles  1  to  12  mm.  long  instead  of  sessile  in  glomerules; 
also  on  having  the  leaves  equally  tomentose  on  both  sides.  In  considering  a  series  of  collections,  like  those 
at  the  New  York  Botanical  Garden,  some  will  fall  plainly  into  one  or  the  other  if  the  inflorescence  alone  is 
considered,  but  some  specimens  have  both  sessile  and  peduncled  heads  and  the  length  of  the  peduncle  varies 
to  such  an  extent  that  no  two  people  would  separate  all  of  the  material  in  the  same  way.  The  density  of  the 
tomentum  also  shows  much  intergradation  and  does  not  vary  parallel  with  the  inflorescence  characters.  Even 
in  the  type  of  candicans  the  difference  between  the  upper  and  lower  surfaces  of  some  leaves  is  not  noticeable. 
At  the  type  locality  of  floccosa,  namely  Lima,  Montana,  some  plants  have  the  small  heads  of  gnaphalodes,  the 
involucres  only  2.5  cm.  high,  while  others  have  involucres  4  mm.  high,  as  in  candicans.  These  extremes  were 
collected  under  Hall  11570,  and  other  forms  and  intermediates  under  Hall  11363  and  11567,  all  from  near  Lima. 


A,    VULGARIS.  83 

20.  A.  PLODMANi  Rydberg,  N.  Am.  Fl.  34:276,  1916.— .4.  vulgaris  flodmani. 

21.  A.  GHiESBRBGHTi  Rydberg,  1.  c,  271,  1916.— Taken  to  be  an  exceptionally  large-headed  form  of  A. 
vulgaris  mexicana,  the  involucres  4  to  5  mm.  high,  but  perhaps  better  treated  as  a  distinct  variety  related  to 
mexicana.  Known  from  only  a  few  collections  from  Chiapas,  which  is  the  type  locality,  and  the  Federal 
District  of  Mexico. 

22.  A.  GNAPHALODE.S  Nuttall,  Genera  2:143,  1818. — A.  vulgaris  gnaphalodes. 

23.  A.  GNAPHALODES  DivERsiFOLiA  NbIsoh;  Coulter  and  Nelson,  Man.  Rocky  Mt.  569,  1909.— Based  upon 
A.  diver sifolia  Rydberg,  which  see. 

24.  A.  GORMANi  Rydberg,  N.  Am.  Fl.  34:267,  1916. — This  is  exactly  the  elatior  form  of  A.  vulgaris  tilesi 
with  rather  narrow  leaf-lobes,  some  of  which  are  again  toothed  or  divided,  and  only  about  10  disk-flowers. 
The  subspecies  tilesi  must  be  taken  to  include  some  forms  with  entire  leaf-lobes  and  some  with  toothed  or  cleft 
lobes,  as  called  for  by  Rydberg's  description  in  the  North  American  Flora.  The  narrow  leaf-lobes  of  gormani 
can  scarcely  be  admitted  as  a  character  of  subspecific  importance  in  a  species  where  the  foliage  is  so  variable, 
and  the  smaller  number  of  disk-flowers  is  perhaps  due  to  the  age  of  the  type  specimens,  the  heads  of  which  look 
as  though  some  flowers  had  been  lost.     Type  locality,  Lake  Iliamna  region,  Alaska. 

25.  A.  GRACiLENTA  Nelson,  Bull.  Torr.  Club  27:35,  1900. — A.  vulgaris  candicans.  Heads  either  sessile 
and  glomerate  or  short-pediceled;  leaves  equally  white-tomentose  on  both  sides.  Type  locality,  sandy  beaches 
and  banks  of  Yellowstone  Lake. 

26.  A.  GRAVEOLENS  Rydberg,  Bull.  Torr.  Club  24:296,  1897. — A.  vulgaris  discolor,  but  with  greener  leaves 
than  in  the  type  and  these  with  slightly  broader  segments  as  in  the  form  once  called  A.  incompta  Nuttall. 
(See  under  A.  michauxiana  of  this  list.)  The  type  came  from  Long  Baldy,  Little  Belt  Mountains,  Montana, 
but  green  plants  of  this  form  occur  from  the  northern  Rocky  Mountains  nearly  to  the  Pacific  Coast. 

27.  A.  HERRioTi  Rydberg,  1.  c,  37:455,  1910. — A.  vulgaris  heterophylla.  Separated  from  the  douglasiana 
form  of  this  subspecies  on  the  basis  of  its  erect  heads  with  only  5  to  15  flowers  and  the  oblong  involucre.  A 
more  recent  examination  of  one  head  from  the  type  reveals  a  total  of  18  flowers  (7  ray  and  11  disk)  which  brings 
the  number  weO  within  the  limits  for  heterophylla,  as  indicated  in  table  6.     Type  locality,  Edmonton,  Alberta. 

28.  A.  HETEROPHYLLA  Nuttall,  Trans.  Am.  Phil.  Soc.  ii,  400,  1841.  Not  A.  heterophylla  Besser,  1834.— 
A.  vulgaris  heterophylla.  The  original  description  is  so  drawn  as  to  include  both  this  and  subspecies  litoralis. 
The  heads  are  given  as  "  cylindric-ovate  and  small,"  which  applies  better  to  litoralis,  but  the  type  locality  is 
given  as  "Rocky  Mountains  by  stream,"  whereas  litoralis  is  closely  confined  to  a  narrow  coastal  strip.  A 
specimen  at  the  herbarium  of  the  Philadelphia  Academy  of  Sciences  labeled  by  Nuttall  as  from  the  Columbia 
Plains  and  as  a  type  of  his  heterophylla,  is  plainly  litoralis.  Another,  in  the  Gray  Herbarium,  labeled  by  Nuttall 
as  from  the  Rocky  Mountains  by  streams  and  also  as  a  type  of  his  heterophylla,  is  just  as  plainly  the  more  inland 
form  here  treated  as  A.  vulgaris  heterophylla.  The  Philadelphia  specimen  has  smaU,  ovoid,  glabrous  heads; 
the  one  at  the  Gray  Herbarium  has  larger,  hemispheric,  tomentose  heads.  Since  the  locality  as  given  on  the 
Gray  Herbarium  label  agrees  with  that  stated  by  Nuttall  in  connection  with  his  description,  this  specimen  is 
taken  as  the  type.     (See  also  under  A.  hookeriana  and  A.  douglasiana  of  this  list.) 

29.  A.  HOOKERIANA  Besser,  in  Hooker,  Fl.  Bor.  Am.  1 :322,  1833. — Not  positively  identified.  The  original 
description  as  well  as  fragments  and  tracings  at  the  Gray  Herbarium,  apparently  of  the  type,  indicate  a  form 
close  to  A.  vulgaris  heterophylla,  with  heads  of  maximum  size  for  this  subspecies  and  white  stems.  The  leaf 
is  deeply  pinnatifid  with  acute  lobes.  The  type  was  collected  by  Drummond  in  the  Rocky  Mountains  and 
therefore,  even  though  it  might  be  accepted  as  belonging  to  the  same  subspecies  as  the  Pacific  Coast  heterophylla, 
it  represents  an  outlying  form  far  removed  from  the  center  of  distribution.  It  is  largely  because  of  these  doubts 
and  the  facts  of  distribution  that  hookeriana  is  not  here  taken  up  as  the  subspecific  name  of  the  common 
mugwort,  which  ranges  from  British  Columbia  to  Lower  California  and  has  commonly  passed  as  A.  vulgaris 
var.  calijornica  Besser  and  A.  heterophylla  Nuttall.  A.  douglasiana  Besser  is  another  trivial  variation  of  sub- 
species heterophylla.  In  the  North  American  Flora  hookeriana  and  douglasiana  are  both  recognized  as  species 
and  distinguished  from  each  other  on  the  lobing  of  the  leaf,  the  former  having  lower  leaves  deeply  divided  into 
more  or  less  falcate  divisions,  the  latter  having  lower  leaves  with  shorter  lobes  or  teeth  directed  forward.  In 
that  work  hookeriana  was  stated  to  occur  from  Saskatchewan  to  Oregon,  douglasiana  from  Idaho  and  southern 
Washington  to  southern  California.  The  utter  unreliability  of  leaf-characters  in  this  group  has  been  already 
demonstrated  (p.  41).  They  do  not  run  parallel  with  distribution,  as  is  indicated  by  the  presence  as  far  north 
as  Oregon  of  plants  with  nearly  entire  or  few-lobed  leaves  (Grant's  Pass,  Oregon,  July  14,  1887,  Howell),  while 
in  the  south  there  are  plants  in  which  the  leaves  are  deeply  cut  into  spreading  lobes  (Laton,  Kings  County, 
California,  October  25,  1919,  Hall,  and  many  collections  from  around  San  Francisco  and  Monterey  bays), 
and  throughout  middle  and  northern  California  both  forms  are  common.  It  is  not  unusual  to  find  all 
gradations  in  leaf-lobing  on  plants  growing  close  together  (see  text-figs.  3,  7,  and  12).  It  is  true,  however,  that  in 
southern  California,  except  along  the  coast,  the  general  tendency  is  towards  entire  or  short-lobed  leaves.  The 
original  description  of  A.  douglasiana  calls  for  entire  leaves,  but  this  was  probably  due  to  the  collector  having 
taken  only  the  tops  of  the  plants. 


84  GENUS   ARTEMISIA. 

30.  A.  INCOMPTA  Nuttall,  Trans.  Am.  Phil.  Soc.  ii,  7:400,  1841. — A.  vulgaris  discolor.  A  robust  form  with 
broad  segments  to  the  leaves.     (See  diagnosis  under  A.  michauxiana  of  this  list.) 

31.  A.  INDICA  CANADENSIS  Bcsser;  Hooker,  Fl.  Bor.  Am.  1:323,  1833. — A.  vulgaris  typica,  from  description. 

32.  A.  INDICA  MEXICANA  Besser,  Nouv.  Mem.  Soc.  Nat.  Mosc.  3:56,  1834. — A.  vulgaris  mexicana. 

33.  A.  KANSANA  Britton,  in  Britten  and  Brown,  111.  Fl.  3:466,  1S9S. — A  form  of  ,4.  vulgaris  ivrighli  equivalent 
to  A.  carrulhi  of  this  list.  The  type,  which  came  from  the  plains  of  Lane  County,  Kansas  {Hitchcock  302,  NY), 
is  the  common  form  in  Kansas  and  western  Missouri.  There  is  little  doubt  that  it  is  identical  with  carrulhi, 
a  name  apparently  overlooked  by  Britton. 

34.  A.  KENNEDYi  Nelson,  Proc.  Biol.  Soc.  Wash.  18:175,  1905. — .4.  vulgaris  heterophylla.  Type  locaUty, 
Verdi,  Washoe  County,  Nevada.  Well  separated  by  its  author  from  A.  suksdorfi  Piper,  that  is,  from  A. 
vulgaris  litoralis,  but  not  compared  with  true  heterophylla,  which  was  assumed  to  be  identical  with  suksdorfi. 
Even  if  heterophylla  were  so  identified,  there  are  other  names,  notably  hookeriana  and  douglasiana,  which  would 
have  precedence  for  this  subspecies  with  broader  gray  involucres  and  more  numerously  flowered  heads.  (See 
further  under  hookeriana  of  this  list  and  in  Hall,  Univ.  Calif.  Publ.  Bot.  3:218,  1907.) 

35.  A.  LEiBERGi  Rydberg,  N.  Am.  Fl.  34:267,  1916. — This  is  a  variation  of  A.  vulgaris  lindleyana  with 
rather  large  heads  and  perhaps  more  nearly  hemispheric  involucres.  The  size  of  the  heads  is  frequently 
equaled  on  plants  referred  without  hesitation  to  this  variety  and  the  shape  of  the  involucres  is  scarcely  if  at 
all  different.  The  type  specimen  of  leihergi  came  from  Fish  Hook  Ferry,  Oregon,  in  a  region  where  lindleyana 
is  common,  especially  on  stony  stream-banks  which  are  flooded  at  seasons  of  high  water. 

36.  A.  LiNDHEiMERiANA  Scheele,  Linnaea,  22:163,  1849. — A  variation  of  A.  vulgaris  mexicana  approaching 
A.  v.  ludoviciana;  stems  rigid  and  almost  woody;  involucre  only  about  2  mm.  broad.  Type  locality,  dry 
streamway  of  the  Cibolo  River,  15  miles  westerly  from  New  Braunfels,  Texas. 

37.  A.  LINDLEYANA  Besser;  Hooker,  Fl.  Bor.  Am.  1:322,  1833. — .4.  vulgaris  lindleyana. 

38.  A.  LINDLEYANA  BREVIFOLIA  Besser,  1.  c. — A.  vidgaris  lindleyana,  a  late  form  with  short  fascicled  leaves. 

39.  A.  LINDLEYANA  cORONOPUS  Besser,  1.  c. — A.  vulgaris  lindleyana  with  the  leaves  sinuately  cleft. 

40.  A.  LINDLEYANA  LEGITUL^  Besser,  1.  c. — Typical  A.  vulgaris  lindleyana. 

41.  A.  LINDLEYANA  sUBDENTATA  Bcsser,  1.  c. — A.  vulgaris  lindleyana  with  leaves  2  to  5  cm.  long,  2  to  4  mm. 
wide,  irregularly  dentate. 

42.  A.  LONGiFOLiA  Nuttall,  Genera  2:142,  1818. — A.  vulgaris  longifolia. 

43.  A.  LUDOVICIANA  Nuttall,  Genera  2:143,  1818. — A.  vulgaris  ludoviciana. 

44.  A.  LUDOVICIANA  DOUGLASIANA  Eaton,  in  Watson,  Bot.  King.  Expl.  183,  1871. — A.  vidgaris  douglasiana, 
as  to  synonymy. 

45.  A.  LUDOVICIANA  GNAPHALODEs  Torrey  and  Gray,  Fl.  N.  Am.  2:420,  1843. — Based  upon  A.  gnaphalodes 
Nuttall,  here  treated  as  A.  vulgaris  subsp.  gnaphalodes. 

46.  A.  LUDOVICIANA  INTEGRIFOLIA  Nelson,  First.  Rep.  Fl.  Wyo.  138,  1896. — A.  vidgaris  longifolia. 

47.  A.  LUDOVICIANA  LATIFOLIA  Torrey  and  Gray,  1.  c. — A.  vulgaris  gnaphalodes.  Based  upon  A.  purshiana 
latifolia  Besser. 

48.  A.  LUDOVICIANA  LATiLOBA  Nuttall,  Trans.  Am.  Phil.  Soc.  ii,  7:400,  1841. — The  type  not  seen  and  the 
description  indefinite.  According  to  Rydberg  it  is  the  same  as  his  A.  platyphylla,  here  reduced  to  A.  vulgaris 
candicans. 

49.  A.  LUDOVICIANA  sERRATA  Torrey  and  Gray,  1.  c. — Based  upon  A.  serrata  Nuttall,  here  reduced  to 
A.  vulgaris  serrata. 

50.  A.  MEXICANA  Willdenow  in  Sprengel,  Syst.  3:490,  1826. — A.  vidgaris  mexicana. 

51.  A.  MEXICANA  BAKERi  Nelson;  Coult.  and  Nelson,  Man.  Rocky  Mt.  569,  1909. — Based  upon  A.  bakeri 
Greene,  which  see. 

52.  A.  MEXICANA  siLVicoLA  Nelson,  1.  c. — Based  upon  A.  silvicola  Osterhout,  which  see. 

53.  A.  MICHAUXIANA  Besscr;  Hooker,  Fl.  Bor.  Am.  1 :324,  1833.— The  oldest  name  for  the  group  of  forms 
here  assembled  under  A.  vulgaris  discolor,  this  varietal  name  selected  because  of  its  brevity  and  long  usage 
as  a  sp)ecies  in  most  of  the  standard  floras.  This  discolor  group  is  exceedingly  variable  in  habit,  foliage,  and 
color,  thus  giving  rise  to  several  so-called  species.  Specimens  representing  these  are  indicated  in  the  citations 
under  discolor.     The  three  most  divergent  forms  may  be  diagnosed  as  follows: 

Genuine  discolor.  Plant  rather  large,  usually  3  to  5  dm.  high,  leaves  mostly  4  to  8  cm.  long,  deeply 
cleft  into  long  attenuate  segments,  these  mostly  1  to  4  mm.  wide;  inflorescence  loose  and  broad.  Quite 
certainly  the  ecologic  response  to  lower  altitude  and  better  soil  conditions  than  those  obtaining  where 
the  next  form  grows.  Found  along  rivers  and  creeks  or  in  copses.  Common  at  high  altitudes  in  the 
Sierra  Nevada,  but  always  in  moist  sandy  places. 

A.  michauxiana  Besser.  Plant  low,  1  to  3  or  sometimes  4  dm.  high;  leaves  only  1  to  4  cm.  long, 
cleft  into  short  lanceolate  lobes,  these  1  to  4  mm.  wide;  inflorescence  rather  compact,  narrow,  spike- 
like. The  common  reduced  form  of  high  altitudes  which  has  commonly  passed  as  A.  discolor.  Type 
locality.  Rocky  Mountains.  Intermediate  between  this  and  true  discolor,  both  as  to  foliage  and  inflores- 
cence, are  specimens  from  British  Columbia,  Macoun  14591,  11,693,  and  76926  (NY),  and  many  others. 


A.   VULGARIS.  85 

The  form  occurs  south  through  the  Cascade  Mountains  to  Oregon,  but  apparently  does  not  reach 
California. 

A.  incompta  Nuttall.  Plant  robust,3  to  9  dm.  high;  leaves  4  to  8  cm.  long,  cleft  into  long  or  some- 
times short  but  always  comparatively  broad  lanceolate  segments,  these  commonly  3  to  5  mm.  wide; 
inflorescence  loose  and  open,  decidedly  paniculate.  Scarcely  distinguishable  from  genuine  discolor, 
except  by  the  wider  leaf-segments.  Belongs  to  moderate  altitudes,  both  in  the  Rocky  Mountains 
and  in  the  Sierra  Nevada. 

Other  but  still  less  important  forms  are  indicated  in  the  present  list  under  A.  graveolens,  A.  potens, 
A.  tenuis,  and  A.  tenuis  var.  integerrima. 

54.  A.  MiCROCEPHALA  WootoH,  Bull.  Torr.  Club  25:455,  1898. — Because  of  the  earlier  A.  microcephala 
Hildebrand,  this  name  was  changed  by  Wooton  to  A.  albula,  which  see. 

55.  A.  MUELLERi  Rydberg,  ?{.  Am.  Fl.  34:270,  1916. — A  form  of  A.  vulgaris  mexicana  with  the  upper  leaves 
inclined  to  be  wider  (5  to  15  mm.  wide)  and  usually  entire.  The  type  specimen  has  only  upper  leaves,  but 
others  of  the  same  form  in  the  Columbia  University  Herbarium  have  leaves  well  below  the  inflorescence  and 
none  of  these  are  cut.  However,  Pringle's  9848,  from  Hidalgo,  as  represented  at  New  York,  is  almost  identical 
with  the  type  of  muelleri,  except  that  lower  leaves  are  present,  and  these  are  cut  nearly  to  the  base  into  3  long 
linear-attenuate  lobes,  as  in  typical  mexicana.  Evidently  here  as  elsewhere  in  the  species  the  use  of  leaf- 
lobing  as  a  criterion  would  result  in  much  confusion.  The  leaves  of  muelleri  are  strongly  veined  beneath. 
Type  locality,  Orizaba. 

56.  A.  NATRONENSI8  Nelson,  Bull.  Torr.  Club  26:485,  1899.— A.  vulgaris  longifolia.  Type  locality,  Willow 
Creek,  Wyoming. 

57.  A.  NEOMEXicANA  Greene;  Rydberg,  N.  Am.  Fl.  34:279,  1916. — A  narrow-leaved  form  of  A.  vulgaris 
mexicana,  therefore  intermediate  to  subspecies  urighti.  The  leaves,  which  are  green  and  glabrate  above, 
are  up  to  4  mm.  wide  below  the  divisions  and  the  lobes  themselves  are  1  to  2  mm.  wide.  The  inflorescence 
is  more  condensed  than  usual  in  mexicana,  the  main  portion  only  about  2  cm.  broad,  but  in  one  of  the  types 
the  basal  portion  is  more  branched  and  4  cm.  broad.    Type  locality,  Hillsboro  Peak,  Black  Range,  New  Mexico. 

58.  A.  OBTUSA  Rydberg,  1.  c,  274,  1916. — A  leaf-form  of  A.  vulgaris  gnaphalodes,  in  which  the  lower  leaves 
are  pinnately  parted  into  3  to  7  divisions.  Although  these  divisions  are  described  as  oblong  and  obtuse,  they 
of  course  narrow  more  or  less  towards  the  summit  and  are  mostly  mucronate,  so  that  they  approach  too  closely 
the  shape  of  the  divisions  in  other  forms  of  gnaphalodes,  especially  A.  diversifolia.  Type  locality,  Columbia 
River,  Washington. 

59.  A.  PABULARis  Rydberg,  Bull.  Torr.  Club  33:157,  1906. — Based  upon  A.  rhizomata  variety  pabularis, 
which  see. 

60.  A.  PAUCICEPHALA  Nelson,  Bull.  Torr.  Club  27 :35, 1900.— A  variation  of  A.  vulgaris  intermediate  between 
the  subspecies  candicans  and  ludoviciana.  The  large  heads  with  involucres  4  mm.  high  and  the  3  mm.  long 
disk-corollas  seem  to  ally  it  more  closely  with  the  former,  but  the  tomentum  is  as  sparse  as  in  the  latter.  Said 
to  be  distinguished  by  its  tufted  cespitose  habit  and  its  low  erect  stems.  Nelson  found  40  to  60  flowers  in  a 
head;  recent  counts  of  2  heads  of  type  material  indicated  totals  of  23  and  27  flowers  respectively.  Type  locality, 
near  Yellowstone  Lake,  on  the  banks  of  a  tributary  creek. 

61.  A.  PLATYPHYLLA  Rydberg,  N.  Am.  Fl.  34:275,  1916. — A  foliage  variation  of  A.  vulgaris  candicans, 
the  lower  and  middle  leaves  cuneate-obovate  and  with  a  few  short  wide  lobes  or  teeth  above  the  middle. 
Very  striking  in  its  extreme  development,  but  thoroughly  intergrading  with  typical  candicans  at  the  type 
locality,  namely,  Spokane,  Washington,  and  in  the  surrounding  country,  as  evidenced  by  an  extensive  series 
of  specimens  collected  by  Miss  Evelyn  Moore  (Herb.  Univ.  Calif.). 

62.  A.  POTENS  Nelson,  Bot.  Gaz.  54:418,  1912. — A.  vulgaris  discolor.  This  is  very  close  to  the  original 
discolor  form  and  is  not  at  all  of  the  michauxiana  type,  so  often  taken  as  typical  discolor  (see  under 
michauxiana  of  this  list).  The  lower  leaves  are  mostly  wanting  from  specimens  of  the  type  collection,  but 
a  few  withered  ones  have  lobes  again  toothed  and  in  earlier  leaves  the  foliage  is  probably  twice-cut. 
According  to  Nelson,  potens  is  herbaceous  to  the  ground  and  grows  on  dry  saline-gravelly  clays  of  the 
plains.    Type  locality,  Mackay,  Idaho. 

63.  A.  PREscoTTiANA  Besscr;  Hooker,  Fl.  Bor.  Am.  1:324,  1833. — Apparently  known  only  from  plants 
collected  by  Douglas  in  northwest  America.  At  the  herbarium  of  the  New  York  Botanical  Garden  is  a  drawing 
and  fragment  from  a  plant  at  Kew  collected  by  Douglas  near  the  Grand  Rapids  of  the  Columbia  in  1825. 
These  are  said  to  correspond  exactly  with  the  type  in  the  Lindley  Herbarium.  From  this  material  and  the 
description  it  seems  that  prescottiana  is  very  close  to  A.  vulgaris  virighti,  but  differs  in  the  strictly  racemose 
arrangement  of  the  heads.  This  character  suggests  subspecies  lindleyana,  but  the  foliage  is  very  different, 
the  leaves  and  their  lobes  being  almost  filiform  and  revolute.  The  involucre  is  3.5  mm.  high  and  nearly 
5  mm.  broad.     Further  collections  are  needed  before  the  exact  placing  of  this  form  can  be  made. 

64.  A.  PRiNGLEi  Greenman,  Proc.  Am.  Acad.  40:50,  1904. — A  Mexican  variation  of  A.  vulgaris  wrighti. 
The  large  heads  are  arranged  in  a  racemiform  panicle,  the  number  of  heads  reduced,  and  the  number  of  flowers 
in  each  head  increased.     In  the  type  specimen  the  involucres  are  3  mm.  high  and  broad,  this  being  about 


86  GENUS   AHTEMISIA. 

the  average  for  wrighli,  but  in  other  plants  from  near  the  type  locality  (Eulalia  Plains,  September  29,  1885, 
Wilhinson,  US  227800),  the  height  and  breadth  are  4.0  and  3.8  mm.,  respectively.  As  is  seen  from  table  6, 
the  total  number  of  flowers  is  about  the  maximum  for  subspecies  urighti,  while  the  number  of  ray-flowers  is 
considerably  higher  than  in  any  other  collection  examined.  In  the  Eulalia  Plains  specimens,  however,  the 
proportion  between  the  number  of  flowers  in  ray  and  disk  is  about  normal,  but  the  total  is  astonishingly  high, 
there  being  10  to  14  in  the  ray  and  24  to  28  in  the  disk.  This  is  so  exceptional  that  the  counts  have  not  been 
entered  in  the  table.     The  type  is  from  plains  near  the  city  of  Chihuahua,  Pringle  625  (Gr). 

65.  A.  PUDICA  Rydberg,  Bull.  Torr.  Club  32:130,  1905. — A.  vulgaris  gnaphalodes.  A  form  with  thinnish 
leaves,  loosely  branched  inflorescence,  and  nodding  heads,  such  as  to  be  expected  in  moist  shady  places.  The 
most  striking  character  lies  in  the  inflorescence,  which  is  composed  of  many  long,  erect  racemiform  branches. 
But  this  may  be  due  in  some  cases  to  injury  to  the  growing  tip  of  the  central  axis,  thus  causing  an  exceptional 
development  of  the  branches.  Such  injury  is  plainly  evident  in  some  specimens  on  the  type  sheet,  as  also 
among  duplicates  of  the  type,  while  other  specimens  of  the  same  collection  show  no  evident  injury.  Type 
locality,  Gunnison,  Colorado. 

66.  A.  PUMILA  Nuttall,  Trans.  Am.  Phil.  Soc.  ii,  7:399,  1841.— Not  A.  pumila  Link  1822.  A  reduced  form 
of  A.  vulgaris  lindleyana  only  1  to  1.5  dm.  high.  Type  locality,  in  the  Rocky  Mountains,  Lewis  River,  by 
ponds  or  in  depressions. 

67.  A.  PUESHIANA  Besser,  in  Hooker,  Fl.  Bor.  Am.  1:323,  1833. — A.  vulgaris  gnaphalodes.  The  leaves  are 
supposedly  broader,  but  since  the  types  of  gnaphalodes  are  wanting  all  but  the  upper  leaves,  this  can  not  be 
verified  and,  indeed,  is  of  no  importance  in  view  of  the  wide  range  of  variation  in  leaf-width.  According  to 
Rydberg  (N.  Am.  Fl.  34:273,  1916),  the  flowers  over  the  range  assigned  to  purshiana  are  light-brown  or  yel- 
lowish, while  true  gnaphalodes,  which  is  assigned  only  to  districts  from  the  Rocky  Mountains  east,  has  dark- 
brown  or  purplish  coroUas.  But  even  according  to  this  discriminating  authority,  purshiana  sometimes  occurs 
as  far  east  as  Nebraska.  While  it  seems  to  be  true  that  the  corolla-color  is  usually  lighter  in  plants  from  west 
of  the  Rocky  Mountains,  there  is  much  variation  in  the  shade  and  the  criterion  is  diflScult  of  application, 
especially  to  dried  specimens  (see  under  Criteria,  p.  39).  The  type  locality  of  A.  purshiana  is  plains  of  the 
Saskatchewan. 

68.  A.  PURSHIANA  ANGUSTIFOLIA  Besser,  1.  c. — Probably  a  very  narrow-leaved  form  of  A.  vulgaris  longifolia. 
Type  locality.  Red  River. 

69.  A.  PURSHIANA  LATIFOLIA  Besser,  1.  c. — A.  vulgaris  gnaphalodes,  from  the  description.  (See  A.  purshiana 
of  this  list.) 

70.  A.  REDOLENS  Gray,  Proc.  Am.  Acad.  21:393,  1886. — A.  vulgaris  redolens. 

71.  A.  REvoLUTA  Rydberg  N.  Am.  Fl.  34:272,  1916. — A.  vulgaris  mexicana.  The  leaves  are  divided  into 
very  narrow  lobes  (2  to  4  mm.  wide)  and  the  margins  of  these  are  more  noticeably  revolute  than  in  most  speci- 
mens.   Apparently  a  response  to  strongly  xerophytic  conditions.    Type  locality,  near  the  city  of  Chihuahua. 

72.  A.  RHizoMATA  NclsoH,  BuU.  Torr.  Club  27:34,  1900. — A  variation  of  A.  vulgaris  gnaplialodes  with  inter- 
rupted inflorescence,  semiwoody  rhizomes,  and  usually  narrow  leaves.  Found  on  low  saline  flats  adjacent  to 
streams.     Type  locality,  Sweetwater  River,  Wyoming. 

73.  A.  RHIZOMATA  PABULARis  Nelson,  1.  c,  1900. — A  slender  competition-form  of  A.  vulgaris  gnaphalodes, 
the  types  from  saline  draws  of  the  Red  Desert  of  Wyoming,  growing  with  grasses.  Leaves  only  2  to  5  mm. 
wide.  According  to  Rydberg  (N.  Am.  Fl.  34:273,  1916),  the  corollas  are  light-brown  as  contrasted  with 
the  dark-browTi  corollas  of  gnaphalodes,  but  those  on  the  type  sheets  appear  dark-brown  or  nearly  purplish. 

74.  A.  SELENGENsis  Turczaiiinov;  Besser,  Nouv.  Mem.  Soc.  Nat.  Mosc.  3:50,  1834. — This  Eurasian  species 
has  been  accredited  to  North  America  by  Rydberg  (N.  Am.  Fl.  34:266,  1916)  on  the  basis  of  supposedly 
introduced  plants  collected  at  Lower  Albina,  near  Portland,  Oregon  (Sheldon  1115,  NY,  US).  There  is  good 
reason  to  believe,  however,  that  these  plants  represent  one  of  the  many  forms  of  A.  vulgaris  heterophylla,  which 
is  common  in  Oregon.  The  lower  leaves  are  wanting,  so  that  there  is  no  evidence  of  the  double  lobing  of  true 
selengensis.  The  upper  leaves  can  be  almost  duplicated  in  native  west-American  forms  (see,  for  example, 
the  figures  on  p.  41).  The  heads  are  small  for  heterophylla,  but  they  are  immature  and  not  smaller  than  on 
many  native  plants  at  the  same  stage.  When  compared  with  European  material  of  true  selengensis,  these  Oregon 
plants  are  seen  to  possess  the  same  general  appearance,  and  especially  the  remarkably  smooth  upper  surface 
of  the  leaves.  But  that  species,  or  rather  form,  for  it  is  often  considered  a  minor  variation  of  typical  A.  vulgaris, 
has  characteristics  not  found  in  these,  especially  the  presence  of  1  or  2  pairs  of  stipule-like  lobes  on  the  lower 
part  of  the  petiole.  These  structures  are  almost  universally  absent  from  heterophylla.  The  petiole  in  the 
Oregon  plants  referred  to  selengensis  is  devoid  of  lobes,  although  there  are  a  few  reduced  leaves  in  the  axils 
which  may  easily  be  mistaken  for  lobes.  Even  if  selengensis  can  be  demonstrated  to  be  distinct  from  A.  vulgaris 
typica,  its  admission  to  the  North  American  flora  may  await  further  evidence. 

75.  A.  SERRATA  Nuttall,  Genera  2: 142,  1818. — A.  vulgaris  serrala. 

76.  A.  siLVicoLA  Osterhout,  Bull.  Torr.  Club  28:645,  1901. — Best  referred  to  A.  vulgaris  ludoviciana,  but 
the  leaves  mostly  entire,  very  green  above,  and  the  heads  rather  large.  Reduced  to  a  variety  of  mexicana 
by  Nelson,  but  lacks  the  long  and  narrow  leaf-lobes  which  furnish  the  only  distinguishing  feature  of  that  sub- 
species.    Rather  common  in  partial  shade  in  Colorado.     Type  locality,  Maclntyre  Creek,  Colorado. 


A.    VULGARIS.  87 

77.  A.  8UBGLABRA  Nelson,  Bull.  Torr.  Club  27:36,  1900. — A  green  variation  from  A.  vulgaris  discolor. 
The  same  as  A.  graveolens  of  this  list.  Type  locality,  stony  banks  of  Yellowstone  River,  near  Yancey's,  Yellow- 
stone Park. 

78.  A.  suKSDORFi  Piper,  Bull.  Torr.  Club  28:42,  1901.— A.  vulgaris  liloralis.  The  type  collection  of  both 
is  the  same. 

79.  A.  SULCATA  Rydberg,  N.  Am.  Fl.  34:270,  1916. — A.  vulgaris  mexicana.  Separated  chiefly  because  of 
the  grooved  stems  and  shining  glabrate  involucres.  The  stems  are  nearly  always  more  or  less  grooved  in 
mexicana  and  the  pubescence  of  the  involucre  is  too  variable  to  furnish  a  good  criterion.  Type  locality,  Casas 
Grandes,  Chihuahua. 

80.  A.  TENUIS  Rydberg,  Mem.  N.  Y.  Bot.  Card.  1 :431,  1900.— Referred  to  A.  vulgaris  discolor.  A  slender, 
small-headed  form  of  A.  graveolens,  which  in  turn  is  only  a  green  variation  of  discolor.  The  heads  are  erect. 
Originally  compared  with  A.  lindleyana,  but  the  paniculate  inflorescence  and  the  double  lobing  of  at  least 
some  of  the  leaves  will  serve  to  distinguish  it.     Type  locality,  Emigrant  Gulch,  Montana. 

81.  A.  TENUIS  INTEGEERIMA  Rydberg,  1.  c,  432,  1900. — Probably  a  chance  variation  of  the  preceding,  with 
which  the  type  and  only  specimen  was  collected.  Lower  leaves  wanting,  but  the  upper  ones  remarkably  entire. 
Type  locality.  Emigrant  Gulch,  Montana. 

82.  A.  TEXANA  Rydberg,  N.  Am.  Fl.  34 :  274,  1916.— A  leaf  form  of  A.  vulgaris  gnaphalodes,  differing  from  the 
type  only  in  the  more  deeply  cleft  foliage.  The  heads  are  of  minimum  size,  about  3  mm.  high;  otherwise  very 
close  to  the  form  called  A.  diversifolia  Rydberg.     Type  locahty,  Colorado,  Texas. 

83.  A.  TiLEsi  Ledebour,  Mem.  Acad.  St.  Petersb.  5:568,  1805. — A.  vulgaris  tilesi. 

84.  A.  TILESI  ARCTiCA  Besser,  Hooker,  Fl.  Bor.  Am.  1:324,  1831. — A  form  of  A.  vulgaris  tilesi  with  entire, 
short,  and  obtuse  leaf-lobes.     From  the  arctic  literal  of  North  America. 

85.  A.  TILESI  ELATioR  Torrey  and  Gray,  Fl.  N.  Am.  2:422,  1843. — A  form  of  A.  vulgaris  tilesi  with  the 
panicle  more  developed  and  far  exceeding  the  leaves.  Apparently  the  only  form  from  Montana  and  Oregon 
to  British  Columbia,  whereas  typical  tilesi  belongs  to  regions  farther  north  and  especially  around  Bering  Sea. 
But  the  elongated  inflorescence  of  typical  elatior  also  occurs  in  the  north,  for  example:  Walker  1077  from  Chil- 
kat  Valley;  1891  Turner,  from  Porcupine  River;  and  Blaisdell  80,  from  Nome.  Intermediate  forms  and  specific 
localities  are  indicated  in  the  coDections  cited  of  subspecies  tilesi.    Type  locality,  subarctic  America. 

86.  A.  TILESI  UNALASCHENSis  Besser,  Linnaea  15:106,  1841. — One  of  the  many  foliage  variations  of  A. 
vulgaris  tilesi.  The  main  leaves  are  described  as  deeply  trifid,  the  lanceolate,  acute  lobes  sparsely  and  unequally 
dentate.     Type  locality.  Island  of  Unalaska. 

87.  A.  UNALASKENSis  Rydberg,  N.  Am.  Fl.  34:266,  1916.— A  form  of  A.  vulgaris  tilesi;  the  stems  tall  and 
heads  in  a  loose  elongated  panicle,  therefore  closely  resembUng  the  form  here  listed  as  elatior.  But  it  differs 
from  all  others  in  having  the  lower  leaves  with  approximate  divisions  and  therefore  appearing  almost  palmate, 
and  the  leaves  exhibit  the  extreme  of  dissection.  The  type  is  from  the  island  of  Unalaska,  Macoun  (Herb. 
Geol.  Surv.  Canada,  20625).  The  writers  have  seen  only  a  photograph  and  piece  of  the  type  deposited  at  the 
New  York  Botanical  Garden  Herbarium. 

88.  A.  UNDERWOODI  Rydberg,  Bull.  Torr.  Club  32:129,  1905. — A.  vulgaris  ludoviciana.  This  is  a  foliage- 
form,  the  leaves  rather  narrower  than  the  average  and  pinnately  parted.  Such  forms  occur  throughout  most  of 
the  range  of  ludoviciana,  but  especially  in  the  arid  mountains  and  foothills  of  Nevada,  California,  and  the 
Southwest.  Some  Californian  plants  referred  here  by  Rydberg  are  narrow-leaved  forms  of  A.  v.  heterophylla. 
Type  locality,  Ouray,  Colo. 

89.  A.  VULGARIS  AMERICANA  Besser,  Linnaea  15:105,  1841. — Two  subspecies  of  A.  vulgaris  are  included  in 
the  original  description.  The  former  of  these,  judging  from  the  description  and  distribution,  is  equivalent  to 
subspecies  tilesi  (the  form  known  as  elatior) ;  the  other  is  subspecies  mexicana,  as  indicated  by  a  portion  of  the 
original  specimen  collected  by  Engelmann. 

90.  A.  VULGARIS  var.  californica  Besser,  Linnaea  15:91,  1841.— A.  vulgaris  heterophylla.  Besser's  name 
gives  the  first  correct  combination  according  to  the  International  Code,  if  treated  as  a  variety.  Type 
locality,  San  Francisco. 

91 .  A.  vulgaris  douglasiana  Rydberg,  N.  Am.  Fl.  34 :  268, 1916.— As  synonym.  This  is  an  evident  slip  for 
A.  ludoviciana  var.  douglasiana,  since  the  former  combination  does  not  appear  in  the  pubhcation  referred  to  by 
Rydberg. 

92.  A.  vulgaris  var.  gnaphalodes  O.  Kuntze,  Revisio,  309,  1891.— A.  vulgaris  subspecies  gnaphalodes. 

93.  A.  vulgaris  var.  litoralis  Suksdorf,  Deuts.  Bot.  Monats.  18:98, 1900.— A.  vulgaris  subspecies  liloralis. 

94.  A.  vulgaris  var.  ludoviciana  O.  Kuntze,  1.  c,  309,  1891.- A.  vulgaris  ludoviciana. 

95.  A.  vulgaris  var.  mexicana  Torrey  and  Gray,  Fl.  N.  Am.  2 :  421,  1843.— A.  vulgaris  subspecies  mexicana. 

96.  A.  vulgaris  tilesi  Ledebour,  Fl.  Rossica  2:586,  1846.     A.  vulgaris  subspecies  tilesi. 

97.  A.  VULGARIS  vuLGATissiMA  Bcsser  in  Hooker,  Fl.  Bor.  Am.  1:322,  1883.— Type  specimen  not  seen; 
probably  to  be  identified  with  one  of  the  forms  of  A.  vulgaris  tilesi.    Type  locality,  Northwest  America. 

98.  A.  WEiGHTi  Gray,  Proc.  Am.  Acad.  19:48,  1883.— A.  vulgaris  wrighti. 

99.  Oligosporus  mexicanus  Lessing,  Syn.  Gen.  Compos.  264,  1832.— Based  upon  A.  mexicana  Willdenow, 
that  is,  A.  vulgaris  mexicana. 


88 


GENUS  ARTEMISIA. 


Invol.  about 
Amm.High;\v3. 
Invol.  3-3.5  mm.      tending  to  caudate 
high 


Lvs. equally  Toment-       Lvs.  green 
ose  on  both  sides,         above, evenly 
not  evenly  serrate^         serrate 


Panicle  broad;  Lvs.tomentose 
fls.15-20  above-,  f  la.  20-30 


Heads  reduced,  15-50 
flowered  ;  invol.  3-4  mrr 
high  ;  lvs,  with  toothed 


Heads  reduced, e-30- 


or  cleft  spreading  lobes,  [lowered;  invol.  3- 
i-4cm.  wiae,  green  or  ^'9^'  Ivs.ent.re  or  w,th 

whifeabbve    \  entire  lobes,  mostly 

2.5  cm.  or  more  wide, 
green  above 


Heads  reduced,  12-25- 
flowered;  invol.  aS-Amm. 
high;  lvs.  with  toothed  or 
cleft  ascending  lobes,  3-7 
cm.  wide,  green  above 


Heads  reduced,  10- 
30- flowered  ,  invol. 
about  3  mm.  high 
(4mm.  in  A);  lvs.  en- 
tire or  with  entire 
lobes,  mostly  1  cm.  or 
less  wide  t+ lobes), 
green  or  white  above 


Heads  large,  zs-so-fTowered; 
invol.  ^-5  mm.  high^  lvs.  entire 
to  2-cleft,  I-  2  cm.  wide  (+lobes), 
hlte-tomentose  on  both  sides 


Fio.  9. — Phylogenetic  chart  of  the  subi^pecies  of  Artemisia  vulgaria. 


A.    VULGARIS.  8VI 

RELATIONSHIPS. 

The  species  of  Artemisia  most  closely  related  to  A.  vulgaris  are  indicated  on  the  chart 
(fig.  9).  A.  alaskana,  A.  franserioides,  and  A.  stelleriana,  although  assembled  close 
to  vulgaris  in  the  diagram,  are  believed  not  to  be  directly  concerned  with  its  origin, 
since  these  species  represent  divergent  phylogenetic  lines.  None  of  them  indicate  any 
tendency  towards  intergradation  with  the  forms  now  under  consideration.  On  the  other 
hand,  the  group  consisting  of  A.  parryi,  A.  macrobotrys,  A.  norvegica,  and  A.  senjavinensis 
seems  to  have  had  an  origin  very  close  to  that  of  vulgaris.  It  is  not  necessary  here  to 
discuss  in  detail  the  relationship  of  this  assemblage  to  vulgaris,  since  this  has  been  done 
elsewhere.  It  should  here  be  noted,  however,  that  in  considering  this  group  as  a  whole, 
certain  forms  of  vulgaris  come  the  nearest  to  representing  the  original  primitive  stock. 
This  is  because  each  of  the  others  possesses  certain  features  indicative  of  an  extreme 
development  along  one  or  more  lines.  Therefore  none  of  them  can  be  considered  as 
primitive.  It  seems  either  that  the  earlier  evolutionary  stages  have  entirely  disappeared, 
or  that  they  have  not  as  yet  been  discovered  by  botanical  collectors.  Although  this 
dropping  out  of  the  earlier  forms  has  resulted  in  the  production  of  some  5  rather  sharply 
defined  and  non-overlapping  species^ — or  more  if  Asiatic  forms  are  taken  into  account — it 
is  not  to  be  assumed  that  these  are  widely  separated  phylogenetically,  or  that  all  can  be 
defined  with  absolute  certainty.  On  the  contrary,  some  of  them  differ  from  certain 
subspecies  of  vulgaris  only  by  features  so  subtle  that  a  close  phylogenetic  analysis  is 
necessary  in  order  to  retain  them  in  specific  rank.  Thus,  for  example,  A.  parryi  closely 
simulates  A.  vulgaris  discolor  and  A.  v.  lindleyana,  yet  from  its  geographic  distribution 
and  morphologic  characters  it  is  seen  that  its  connection  with  vulgaris  stock  is  not 
through  these  specialized  varieties,  but  through  more  primitive  forms  probably  now 
extinct.  While  the  other  enumerated  species  are  of  close  kin  to  vulgaris,  all  can 
similarly  be  shown  to  belong  to  lines  which  diverged  from  the  parent  stock  before  the 
numerous  subdivisions  of  this  species  began  to  differentiate. 

Artemisia  vulgaris  is  the  most  variable  of  all  the  Artemisias,  at  least  as  far  as  the  Amer- 
ican species  are  concerned.  When  the  subspecies  are  arranged  in  what  appears  to  be  a 
natural  phylogenetic  sequence,  as  is  attempted  in  the  accompanying  diagram,  it  is  seen 
that,  although  the  extremes  are  far  apart,  all  are  so  closely  held  together  by  forms  repre- 
senting intermediate  steps  that  no  place  is  found  where  a  line  can  be  drawn  that  will 
separate  the  multitude  of  forms  into  well-defined  species.  This  condition  is  not  so  re- 
markable, however,  when  it  is  noted  that  the  variations  are  not  in  essential  features  but 
chiefly  in  characters  of  foliage,  size  of  heads,  number  of  flowers,  and  amount  of  pubes- 
cence. Some  of  the  resultant  variations  are  very  unlike  in  appearance,  but  it  is  not 
difficult  to  see  how  all  have  had  a  common  origin  in  no  far  distant  past.  As  an  aid  to 
this  it  should  be  remembered  that  not  all  of  the  known  forms  are  indicated  on  the  chart, 
but  only  those  which  are  sufficiently  noteworthy  to  be  ranked  as  subspecies.  Between 
many  of  these,  still  smaller  variations  are  known,  most  of  which  are  enumerated  in  the 
text  under  the  heading  of  "Minor  variations."  These  represent  the  still  shorter  steps 
in  the  progress  of  evolution  within  the  species.'  Nearly  all  of  them,  as  well  as  all  of  the 
accepted  subspecies,  have  at  one  time  or  another  been  classed  as  distinct  species,  so  that 
in  all  some  80  described  units,  as  well  as  many  more  undescribed  ones,  are  available  for 
study.  It  is  thus  seen  that  Artemisia  vulgaris  offers  one  of  the  most  promising  fields 
for  phylogenetic  researches.  In  some  portions  of  this  field  all  intermediate  stages  are 
still  available,  so  that  even  the  direction  of  evolution  can  be  worked  out  with  a  reasonable 
degree  of  certainty  by  means  of  field  observations,  mapping  of  distribution,  and  statis- 
tical analyses.  In  other  places  small  gaps  occur.  In  some  instances  these  have  been 
bridged  through  the  production  of  the  intermediate  stages  by  experimental  methods. 
In  only  a  few  places  are  the  lines  of  descent  so  broken  that  they  can  not  be  satisfactorily 


90  GENUS   ARTEMISIA. 

reconstructed.  It  should  not  be  inferred  from  these  remarks,  however,  that  the  accom- 
panying chart  is  presented  with  confidence  as  to  its  accuracy.  Rather  is  it  to  be  looked 
upon  as  a  first  attempt  to  unravel  the  tangled  skein  of  relationships  in  this  complex 
species,  and  to  arrange  into  some  sort  of  natural  sequence  the  numerous  taxonomic  units 
bequeathed  by  the  descriptive  botanists.  Many  changes  in  grouping,  and  especially  in 
direction,  will  doubtless  be  found  necessary  as  further  evidence  is  brought  to  bear  upon 
this  problem. 

The  most  primitive  of  all  of  the  subspecies  of  A.  vulgaris  is  probably  tilesi.  This 
has  large  heads  with  numerous  flowers,  a  tendency  towards  twice-pinnatifid  leaves,  and 
a  northern  distribution.  The  cumulative  evidence  indicates  that  this  group  of  American 
Artemisias  had  its  origin  far  to  the  north  and  that  the  forms  have  been  multiplied  as 
the  stock  spread  to  the  south.  If  the  opposite  were  assumed,  namely,  that  the  southern 
forms  are  the  older,  while  the  northern  ones  are  the  derived  strains,  then  serious  difficul- 
ties would  be  encountered  in  interpreting  the  origin  of  the  character  differences.  In  the 
present  case  it  seems  fairly  certain  that  the  large-headed  forms  like  tilesi,  which  occur 
only  in  the  north,  have  given  rise  to  the  more  southerly  forms  with  fewer  flowers  to  the 
head  and  with  other  reductions. 

Assuming  that  the  subspecies  Wesi  was  early  established  in  the  north,  it  is  not  unlikely 
that  it  represents  a  still  more  primitive  type  which  ranged  far  to  the  east  and  west  in 
arctic  and  subarctic  regions.  One  of  the  derivatives  of  this  form,  or  perhaps  of  tilesi 
itseK,  is  subspecies  typica.  This  nomenclatorial  type  of  the  species  is  native  in  north- 
central  Asia  and  is  well  known  in  Europe  as  an  introduced  plant.  It  differs  from  tilesi  in 
the  usually  reduced  size  of  the  heads  and  in  the  reduced  numbers  of  flowers  in  the  indi- 
vidual head,  as  indicated  in  table  6,  but  it  retains  the  character  of  twice-dissected  leaves. 
At  the  base  of  the  petiole  are  2  stipule-like  lobes,  an  almost  unique  feature  in  the  genus, 
but  these  structures  are  occasionally  found  also  in  tilesi  (Dutch  Harbor,  Unalaska,  Van 
Dyke  101,  Gr),  as  indicated  in  figure  10.  Additional  connecting  forms  may  be  expected 
as  the  flora  of  Siberia  and  Alaska  become  better  known.  There  are  also  frequent  sug- 
gestions of  a  connection  between  typica  and  some  of  the  other  West- American  subspecies, 
notably  heterophylla.  The  similarity  in  the  foliage  is  indicated  in  figure  7,  p.  74.  Even  the 
stipule-like  basal  lobes  are  sometimes  present  in  specimens  referable  only  to  heterophylla 
(northern  Idaho,  Sandberg  822,  US)  and  they  are  rather  common  in  A.  v.  discolor}  It  is 
believed,  however,  that  these  similarities  are  due  to  the  persistence  of  ancestral  traits 
rather  than  to  any  immediate  phyletic  connection.  From  these  considerations  it  is  con- 
cluded that  typica  is  an  offshoot  from  the  original  stock  best  represented  by  tilesi  and  that 
it  is  not  directly  connected  with  any  other  American  form.  It  is  thus  a  western  diver- 
gence which  has  reached  our  territory  only  as  an  introduction  by  way  of  Europe,  and  for 
this  reason  it  is  indicated  on  the  chart  as  lying  entirely  to  one  side  of  the  other  subspecies. 
It  should  be  noted,  however,  that  typica  is  sometimes  considered  as  native  in  the  North- 
east, and  that  if  introduced  it  reached  America  a  long  time  ago  (Fernald,  Rhodora  2: 135, 
1900).  Notwithstanding  its  close  connection  with  tilesi,  as  shown  above,  there  is  a  wider 
phylogenetic  gap  between  these  two  subspecies  than  is  usually  the  case  among  series  of 
forms  as  here  set  forth. 

Another  subspecies  is  conceived  as  diverging  from  tilesi,  but  in  a  different  direction. 
This  is  candicans,  of  the  northwestern  United  States  and  adjacent  Canada,  where  its  range 
meets  that  of  tilesi.  Apparently  it  has  given  rise  to  none  of  the  others,  although  there 
is  some  evidence  of  a  connection,  especially  with  gnaphalodes.  The  subspecies  candicans 
scarcely  differs  from  tilesi,  except  in  the  presence  of  a  copious  white  tomentum  on  the 
upper  as  well  as  on  the  lower  surface  of  the  leaves.     This  appearance  of  paired  subspecies, 

'  The  nature  of  the  false  stipules  in  Artemisia  vulgaris  and  other  plants  has  been  investigated^by  Schiller  (Sitzb.  Akad. 
Wiss.  Wien,  112:793-819,  1903). 


A.    VULGARIS. 


91 


differing  only  in  the  tomentum,  recurs  at  a  number  of  places  in  the  species,  as,  for  exam- 
ple, between  ludoviciana  and  gnaphalodes  and  also,  but  with  the  addition  of  other  tenden- 
cies, between  discolor  and  flodmani.  When  the  former  pair  is  reached  in  this  discussion, 
evidence  will  be  adduced  for  considering  the  heavily  tomentose  as  the  more  advanced 
type. 


Fio.  10. 
Leaves  of  Artemisia  vul- 
garis typica  and  A.  v  tilesi: 
a,  typica  from  Rochester, 
New  York,  August  16, 
1897,  House  (Gr);  6,  tilesi 
from  Dutch  Harbor,  Una- 
laska.  Van  Dyke  101  (Gr). 
Both  X  0.5. 


Aside  from  tilesi  itself,  the  subspecies  thus'far  considered  have  not  led  to  other  well- 
marked  variations,  however  numerous  their  minor  forms  may  be.  The  remaining  sub- 
species, on  the  other  hand,  may  be  grouped  around  three  central  ones,  each  of  which 
has  given  rise  to  one  or  more  groups  of  equal  rank  with  itself.  The  first  of  these  is 
discolor,  a  common  subspecies  in  the  western  mountainous  districts.  This  is  widely 
separated  from  tilesi  in  most  taxonomic  treatments  and  is  even  placed  in  a  separate  sec- 
tion of  the  genus  in  the  latest  monographic  account  (Rydberg,  N.  Am.  Fl.  34:245,  1916). 
Yet  in  all  essential  characters  these  two  forms  come  very  close  to  each  other ;  both  have 
short,  twice-dissected  leaves  with  the  same  peculiar  cut  to  the  lobes,  the  involucre  is 
green  in  both,  and  the  heads,  although  averaging  smaller  in  discolor,  exhibit  a  complete 
intergradation  in  this  respect  (see  table  6).  Thus  the  only  characters  left  for  the  dis- 
tinction of  discolor  are  the  usually  smaller  heads  and  the  somewhat  narrower  lobes  of  the 
smaller  leaves.  The  connection  seems  to  be  estabUshed  by  specimens  in  which  the  heads 
are  large,  but  with  all  the  other  characteristics  of  discolor  (Bear  Canon,  Custer  County, 
Idaho,  Nelson  and  Macbride  1521).  In  the  collection  just  cited  the  involucre  is  about 
4  mm.  high  and  4.5  mm.  broad  and  the  number  of  disk-flowers  varies  from  23  to  29.  For 
some  unexplained  reason,  A.  v.  discolor  often  has  been  confused  with  A.  v.  mexicana,  but 
this  latter  has  exceptionally  long  leaves  with  slender,  entire  lobes  and  the  heads  are 
usually  smaller  and  more  tomentose.  The  inflorescence  of  discolor  is  sometimes  very 
similar  to  that  of  A.  v.  lindleyana  and  the  two  are  often  confused  in  the  absence  of  good 
foUage.  This  subspecies  seems  to  intergrade  or  hybridize  also  with  subspecies  gnapha- 
lodes and  ludoviciana,  as  is  indicated  by  a  series  of  specimens  gathered  near  Durant,  in 
western  Montana  (Hall  11579  and  11580  UC). 

Indicated  on  the  chart  as  a  derivative  of  discolor,  but  of  doubtful  origin  is  the  subspecies 
redolens.     If  morphological  characters  alone  were  taken  into  account,  the  two  could  be 


92 


GENUS  ARTEMISIA. 


maintained  as  separate  subspecies  only  with  the  greatest  difficulty.  The  widely  branch- 
ing inflorescence  and  fewer-flowered  heads  make  redolens  an  easily  recognized  unit,  but 
these  features  may  be  only  the  result  of  the  habitat,  since  it  is  thus  far  known  only  from 
the  proximity  of  clififs  in  northern  Mexico.  Because  of  this  wide  geographic  separation 
from  its  nearest  relatives,  redolens  may  stand  as  a  subspecies,  at  least  until  its  ecology  is 
better  understood.  It  was  referred  by  Gray  to  the  section  Dracunculus,  an  error  which 
has  been  already  pointed  out  by  Rydberg  (N.  Am.  Fl.  34:278,  1916).  Another  derivative 
of  the  discolor  group  is  subspecies  flodmani.  This  is  a  local  form  confined  to  western 
Montana  and  adjacent  States.  The  upper  surface  of  its  leaves  has  taken  on  a  heavy 
tomentum  and  the  flowers  in  each  head  have  been  reduced  in  number. 


Fio.  11. 

Leaves  of  ATtemiaia  vulgaris  dis- 
color: a,  from  near  the  base  of  the 
stem,  b,  c,  d,  from  toward  the  summit 
of  the  same  plant.  Yosemite  National 
Park  (73969  UC).  This  is  the  "in- 
compta"  form,  also  known  as  A. 
underwoodi.     All  X  0.8. 


In  its  early  southward  migration,  the  subspecies  tilesi,  which  is  here  considered  as  the 
progenitor  of  all  the  other  native  American  forms,  underwent  modification  in  a  number  of 
its  characters.  Thus,  through  a  simphfication  in  the  cut  of  the  leaf,  together  with  some 
reduction  in  the  leaf-size  and  in  the  size  of  the  heads,  there  was  evolved  the  more  southerly 
subspecies  heterophylla.  This  has  been  variously  known  as  A.  hookeriana  Besser  (1833), 
A.  douglasiana  Besser  (1833),  A.  vulgaris  var.  californica  Besser  (1841),  and  A.  hetero- 
phylla Nuttall  (1841).  The  last  is  here  chosen  for  the  subspecific  name  as  being  the  most 
descriptive  and  the  one  in  most  general  use.  Forms  connecting  heterophylla  with 
tilesi  are  common  where  the  geographical  ranges  of  the  two  overlap  in  southern  Canada 
and  adjacent  United  States.  In  this  area  are  found  specimens  of  tilesi  with  leaves  only 
once-pinnatifid  and  others  in  which  the  size  of  heads,  foliage  characters,  and  habit  are 
such  that  they  might  be  classed  as  either  the  one  or  the  other.  The  overlapping  in  the 
size  of  the  heads  and  in  the  number  of  flowers  per  head  is  brought  out  in  table  6.  The 
types  of  heterophylla  came  from  somewhere  in  Canada  and  were  probably  low  plants  with 
pinnatifid  leaves.  It  is  unfortunate  that  the  types  were  from  near  the  border  of  the  area 
of  distribution,  since  they  do  not  well  represent  the  normal  form  so  common  farther 
south,  especially  from  Washington  to  California.  However,  leaf-tracings  and  a  single 
head  taken  from  the  types  and  preserved  at  the  New  York  Botanical  Garden  can  be 
easily  duplicated  in  California. 

Subspecies  heterophylla  is  comparatively  rare  in  the  northern  Rocky  Mountain  States 
and  entirely  wanting  to  the  south  of  them,  but  to  the  west  it  swings  across  Washington 
nearly  to  the  coast,  is  abundant  in  Oregon  and  California,  and  extends  on  southward 
into  Lower  California.  Because  of  their  more  nearly  entire  leaves,  these  southern  plants 
recently  have  been  referred  to  "A.  douglasiana  Lindley,"  the  type  of  which  came  from 
the  Columbia  River.  This  form,  however,  is  scarcely  distinguishable  except  in  the  her- 
barium, where  specimens  frequently  exhibit  only  the  upper  leaves.  Field  studies  indi- 
cate that  the  lower  leaves  are  probably  never  entire.  It  must  be  said,  however,  that 
southern  specimens  are  likely  to  have  a  larger  number  of  entire  or  only  toothed  leaves 


A.    VULGARIS.  93 

than. northern  ones.  This  does  not  apply  to  coastal  plants,  since  in  these  the  leaves  are 
for  the  most  part  deeply  pinnatifid.  These  facts  are  in  accord  with  the  general  theory 
that  as  the  species  extends  towards  the  south  or  away  from  the  coast  the  foliage  is 
reduced  in  size  and  simplified  in  its  lobing.  Even  in  those  forms  of  heterophylla  which 
have  undergone  the  greatest  amount  of  modification  in  foliage  characters,  the  leaves  are 
still  ample  as  compared  with  those  of  ludoviciana  and  other  varieties  of  dry,  interior  habi- 
tats. In  this  connection  it  should  be  noted  that,  while  heterophylla  often  grows  in  warm, 
arid  districts,  it  there  occupies  stream-banks,  bottom-lands,  and  other  places  where  there 
is  a  reasonable  amount  of  soil  moisture  to  draw  upon.  As  to  the  nature  of  the  lobing 
of  the  foliage,  this  varies  through  all  degrees  from  deeply  pinnatifid  with  widely  spreading 
and  narrow  lobes  to  entire.  Often  a  peculiar  cut  will  be  observed  in  all  of  the  principal 
leaves  of  one  clump  of  plants,  while  an  entirely  different  type  will  be  found  on  neighbor- 
ing plants.  This  seems  to  indicate  the  presence  of  numerous  strains,  possibly  with  hybrids 
between  them.  Apparently  the  only  rational  way  of  organizing  these  leaf-forms  is  by 
the  method  of  genetic  analysis.  Any  attempt  to  classify  them  by  usual  taxonomic 
methods  would  lead  only  to  confusion,  and  it  is  because  of  the  recognition  of  this  that  the 
numerous  so-called  species  of  some  recent  works,  based  upon  leaf-characters  alone,  are 
here  relegated  to  the  category  of  minor  variations.  A  hint  as  to  what  may  be  expected 
in  the  way  of  leaf-forms  is  given  in  figure  3,  p.  41,  and  figure  7,  p.  74. 

In  strong  contrast  to  the  trivial  variations  just  discussed  is  the  subspecies  litoralis, 
a  form  restricted  to  the  vicinity  of  the  coast  from  southern  British  Columbia  to  Mendocino 
County,  California.  It  differs  from  subspecies  heterophylla,  of  which  it  is  a  derivative, 
especially  in  the  narrowed,  shining  involucre  and  in  the  reduced  number  of  flowers. 
Although  the  collections  have  been  numerous,  no  intermediate  forms  have  been  encoun- 
tered. The  absence  of  overlapping  in  the  number  of  flowers  is  indicated  in  table  6,  and 
the  two  may  be  distinguished  without  hesitation  by  an  examination  of  the  involucre 
alone. 

The  remaining  subspecies  differ  from  those  thus  far  discussed  in  the  usually  smaller 
heads  which  have  a  reduced  number  of  flowers.  Their  leaves  are  comparatively  narrow  and 
only  once  pinnatifid  or  toothed  or  often  entire.  This  seems  to  be  a  natural  group  which 
has  originated  from  the  tilesi  stock  and,  spreading  out  over  a  large  area  to  the  southeast 
of  the  range  of  that  primitive  form,  has  now  come  to  occupy  the  Rocky  Mountain  region 
especially,  but  with  extensions  southward  through  Mexico,  east  to  slightly  beyond  the 
Mississippi  River,  and  west  almost  to  the  Pacific  Coast.  This  westward  extension, 
however,  is  much  less  important  than  the  others,  since  the  group  is  not  strongly  repre- 
sented west  of  the  Great  Basin.  During  the  course  of  its  occupancy  of  this  extensive 
area,  and  perhaps  because  of  the  wide  range  of  conditions  here  encountered,  the  group 
broke  up  into  an  innumerable  series  of  forms,  many  of  which  have  been  accorded  specific 
rank  by  taxonomists.  All  of  these  so-called  species  are  based  upon  highly  variable 
characters,  such  as  those  of  the  foliage,  inflorescence,  pubescence,  etc.  Many  of  them 
are  here  mentioned  only  under  minor  variations,  and  some  of  the  less  important  and 
unnamed  ones  are  not  mentioned  at  all,  while  those  which  seem  to  represent  definite 
stages  in  the  development  of  the  species,  or  centers  about  which  the  minor  variations 
may  be  grouped,  are  treated  as  subspecies.  Even  these  accepted  subspecies  are  some- 
times so  closely  interlocking  in  their  characters  that  the  evolutionary  lines  can  not  be 
worked  out  with  certainty  at  this  time.  This  portion  of  the  chart  is  therefore  presented 
more  for  the  purpose  of  indicating  the  characters  used  than  to  show  phyletic  lines. 

The  original  form,  which  in  turn  gave  rise  to  the  others  of  this  group,  seems  to  have 
been  something  now  included  under  the  subspecies  ludoviciana.  The  derivation  of  the 
othera  from  this  can  be  accounted  for  in  accordance  with  the  laws  of  phylogeny  (see 


94  GENUS   ARTEMISIA. 

Bessey's  dicta,  Mo.  Bot.  Gard.  Annals  2:109,  1915),  but  if  the  sequence  were  reversed 
it  would  run  counter  to  these  laws.  Examples  of  this  will  be  given  a  little  farther  on. 
The  subspecies  ludomciana  is  typically  a  form  with  small  heads,  the  principal  leaves  with 
a  few  short  lobes,  as  shown  in  tracings  from  the  type  (fig.  8),  and  an  evident  but  light 
tomentum  on  the  upper  surface  of  the  leaves,  the  lower  surface  heavily  tomentose,  as 
in  all  the  subspecies  of  A.  vulgaris.  The  concept  is  here  extended,  however,  to  include 
the  more  common  form  with  the  upper  surface  of  the  leaves  nearly  or  quite  glabrous; 
also  forms  in  which  the  leaves  are  variously  lobed  or  entire,  since  these  characters 
have  been  demonstrated  to  be  too  subject  to  variation  to  be  of  taxonomic  value. 
Ludoviciana  is  a  derivative  of  tilesi,  and  not  the  other  way  around,  as  seems  evident 
from  its  distribution  and  from  the  specialized  nature  of  its  characters,  i.  e.  the  reduced 
heads,  each  with  a  reduced  number  of  flowers,  the  narrower  and  simply  lobed  leaves, 
and  the  tendency  toward  the  development  of  a  tomentum  on  the  upper  surface  of  the 
leaves. 

A  subspecies  very  close  to  ludoviciana,  and  united  with  it  by  Gray  and  others,  is 
gnaphalodes.  This  differs  in  having  leaves  which  are  heavily  tomentose  on  both  sides, 
a  character  difference  which  ordinarily  would  not  be  considered  as  of  much  value,  yet 
one  which  is  here  found  to  be  the  most  constant  of  all  those  proposed  for  the  breaking 
up  of  this  complicated  group  of  forms.  Sometimes  these  two  subspecies  occupy  adjacent 
habitats.  Subspecies  ludoviciana  then  occupies  the  more  shaded  or  moist  situations, 
the  two  forms  thus  standing  somewhat  in  the  relation  of  ecads  to  each  other.  At  other 
times,  however,  one  will  occupy  vast  extents  of  territory  to  the  complete  exclusion  of  the 
other,  as,  for  example,  on  much  of  the  plains  country  east  of  the  Rocky  Mountains, 
where  in  some  districts  only  gnaphalodes  is  found.  Just  as  ludoviciana  may  be  looked 
upon  as  a  southeastern  or  Rocky  Mountain  development  from  tilesi,  so  gnaphalodes 
may  be  considered  as  the  more  xerophytic  offshoot  from  ludoviciana,  occupying  in  part 
the  same  geographic  area  but  also  extending  farther  towards  the  east.  Various  forms 
of  leaves  taken  from  plants  growing  on  the  same  hillside  are  illustrated  in  figure  12. 

In  the  northerly  part  of  the  Mississippi  Valley  the  gnaphalodes  stock  has  so  modified 
the  leaves  that  these  have  become  elongated  and  drawn  out  at  the  apex  into  a  more 
or  less  tail-like  appendage,  while  at  the  same  time  the  heads  remain  larger  than  usual. 
This  is  subspecies  longifolia.  It  is  easily  recognized  in  its  extreme  development,  but 
frequent  intergrades  reveal  its  undoubted  connection  with  gnaphalodes.  The  leaves 
in  longifolia  are  sometimes  green  on  the  upper  surface.  This  is  brought  about  by  the 
shedding  in  age  of  the  heavy  tomentum  and  hence  does  not  indicate  a  direct  connection 
with  ludoviciana.  Various  stages  in  this  shedding  process  may  be  seen  in  specimens 
collected  at  Lake  De  Smet,  Wyoming  (Nelson  8545,  UC). 

The  most  striking  of  all  of  the  subspecies  of  Artemisia  vulgaris  is  serrata.  This  occurs 
only  in  the  upper  part  of  the  Mississippi  Valley,  where  it  grows  in  good  and  rather  moist 
soil.  It  is  a  larger  plant  than  other  subspecies  of  this  region  and  bears  much  elongated 
panicles  of  rather  small  heads  (see  table  6).  The  principal  distinguishing  characters, 
however,  lie  in  the  leaves.  These  are  remarkably  constant  in  their  lanceolate  shape  and 
in  the  distribution  of  the  pubescence,  the  upper  surface  being  always  green  and  nearly 
or  quite  glabrous,  the  lower  surface  densely  white-tomentose.  The  even  serratures  of 
the  margins  also  are  usually  constant,  but  a  few  collections  exhibit  intermediate  forms 
connecting  with  subspecies  ludoviciana  and  gnaphalodes.  Specimens  referable  to  gnapha- 
lodes, but  with  the  leaves  toothed  somewhat  as  in  serrata  are:  Spring  Grove,  Minnesota, 
Rosendahl  693  (Gr),  and  near  Minneapolis,  Minnesota,  1892,  Aiton  (Gr).  Leaves 
with  margins  intermediate  between  these  two  subspecies  are  illustrated  in  figure  13. 
The  shape  of  the  leaf  is  sometimes  exactly  matched  in  plants  identified  as  subspecies 


A.    VULGARIS. 


95 


ludoviciana,  because  of  the  entire  margins  and  other  characters  (Glenwood,  Minnesota, 
August,  1891,  Taylor,  UC).  While  the  principal  leaves  of  these  are  entire,  the  lower 
exhibit  remote  and  irregular  dentations  not  at  all  comparable  to  the  even  serratures  of 
serrata.     It  seems,  therefore,  that,  while  this  is  an  especially  distinct  form,  and  although 


Fig.  12. 

Variation  in  outline  of  leaves  of  Artemisia  vulgaris 
gnaphalodes.  The  three  leaves  in  each  vertical  row  are 
from  a  single  plant;  the  lowest  leaf  in  each  column  is 
from  near  the  base  of  the  stem,  the  middle  leaf  from 
somewhat  above  midway  of  the  stem,  the  highest  leaf 
from  the  lower  part  of  the  inflorescence.  All  three 
plants  were  growing  within  100  m.  of  one  another  near 
Golden,  Colorado.  The  plant  with  leaves  shown  in 
first  column  was  in  loose  soil  with  rank  vegetation ;  the 
others  on  higher  slopes,  the  soil  hard  and  stony,  the 
surrounding  vegetation  less  rank.  All  of  the  leaves  are 
densely  tomentose  beneath  and  scarcely  less  so  above. 
Plant  at  left  would  be  classed  as  Artemisia  brittoni 
(minor  variation  6)  and  plant  at  right  as  A.  gnaphalodes 
by  those  who  use  leaf  characters  as  spec  " 
All  X  0.4. 


its  exact  origin  can  not  now  be  traced,  its  connection  with  subspecies  ludoviciana  and 
gnaphalodes  is  sufficiently  well  established  to  justify  its  reduction  to  a  subspecies  of  this 
group.    (See  fig.  13,  p.  96.) 

Close  to  ludoviciana  but  usually  recognized  by  its  more  reduced,  spike-hke  inflorescence, 
is  subspecies  lindleyana.     The  plants  of  this  are  often  quite  woody  at  the  base.     Here 


96  GENUS   ARTEMISIA. 

also  belongs  subspecies  mexicana,  which  is  clearly  a  southern  derivative  of  a  ludoviciana- 
like  ancestor  but  marked  by  a  very  leafy  habit,  the  foliage  continuing  well  up  into  the 
inflorescence,  and  by  narrow  leaves  and  lobes,  these  latter  much  elongated  and  with 
finely  revolute  margins.  It  appears  to  be  an  ecologic  type,  but  it  is  so  extreme  and  as 
far  as  known  is  so  well  restricted  geographically  that  it  perhaps  has  subspecific  value. 
According  to  Rydberg,  the  leaves  of  the  type  are  not  revolute,  and  he  therefore  names 
the  common  form  with  revolute  leaves  as  A.  revoluta  (see  p.  86). 

In  the  arid  portions  of  the  southern  Rocky  Mountains  and  northern  Mexico  and 
running  out  onto  the  plains  to  the  southeast  as  far  as  Kansas  is  found  yet  another  deriva- 
tive of  ludoviciana,  namely,  subspecies  wrighli.  This,  also,  is  a  more  xerophytic  type. 
Perhaps  partly  because  of  the  more  arid  conditions  under  which  it  grows,  and  partly 
because  of  the  increased  Ught  intensity,  the  foliage  has  reached  the  extreme  in  the  matter 
of  reduction  of  leaf  surface.     The  leaves  are  small  and  divided  into  almost  fihform  seg- 


Fia.  13. 

Leaves  of  Artemisia  vulgaris  gnaphalodes  and  A.  v.  serrata:  a,  b,  leaves   of 

gnaphalodes  from   Spring  Grove,   Minnesota,   Rosendahl  693  (Gr);  c,   leaf  of 

serrata  from  middle  portion  of  stem,  Fountaindale,  Illinois,  Bebb  (Gr).     All 

X0.8. 


ments.  Because  of  this  notable  narrowing  of  the  lobes,  the  various  forms  here  included 
under  wrighti  have  been  commonly  treated  as  one  or  more  distinct  species,  even  by 
conservative  systematists.  But  intermediate  forms  are  so  plentiful  in  all  of  the  larger 
herbaria  that  they  need  not  even  be  cited,  and  in  the  field  it  becomes  impossible  to  draw 
any  line  between  true  ludoviciana  and  wrighti.  However,  the  latter  may  stand  as  a 
subspecies  to  include  these  small  and  extremely  narrow-lobed  forms  of  the  south.  Within 
the  subspecies  wrighti  may  be  detected  several  minor  variations,  as  indicated  on  page  81. 
In  some  and  perhaps  in  all  of  these,  as  well  as  in  typical  wrighti,  the  basal  leaves  on  sterile 
shoots  are  floccose  with  a  white  tomentum  on  both  surfaces,  quite  regardless  of  the 
nature  of  the  pubescence  on  the  upper  leaves.  Although  this  suggests  a  possible  connec- 
tion with  some  white-leaved  ancestor,  all  of  the  other  evidence  points  to  ludoviciana 
as  the  source  of  this  subspecies. 


A.    VULGARIS. 

-Variation  in  the  subspecies  of  Artemisia  vvlga 


97 


Herbarium. 

No.  of 
bracts. 

No. 
of  ray- 
flowers. 

No. 
of  disk- 
flowers.' 

Total 
flowers.' 

Length 
of  disk- 
corolla. 

Subspecies  lilegi: 

Eastern  Siberia                             ...            

NY 
Gr 

NY 
Gr 
Gr 
Gr 

NY 

NY 

886446  US 

Gr 

NY 

10 

10 

17  13 

12   12 

12 

12 

8  10 

11 

11   11 

9 

9 

10 

13 

17  13 

10     7 

10 

14 

10  15 

13 

8     9 

21 
16 
35 

52  46 

30  15 
37 
35 

28  28 
46 

10  16 
17 

30 
26 
48 
69  59 
40  22 
47 

38  43 
59 

18  25 
25 

mm. 
2.5 
2.7 
2  5 
2.5 
3.5 
3.0 
3.0 
3.0 
2.6 
2.5 
2.0 

Plover  Bay  Siberia 

Dutch  Harbor   Unalaska                              .    .    . 

Hushajak   Alaska 

10 

10 

28 

40 

2.7 

Subspecies  candicans: 

Spokane   Wash                   

Gr 

11621a  CI 

116216  CI 

11548  CI 

1027299  US 

2942  NY 

1027298  US 

NY 

20753  R 

13 
13 
12 
12 
13 
11 

11 
14 

7 
14   10 
10 
11 
12 

6 

7 
10 

18 
35  23 

30 
30 
23 
28 
21 
28 

25 
49  33 
29 
41 
42 
28 

28 
38 

2.5 

2^6 
2.5 
2.5 

2^8 
3.0 
3.0 

Near  Sexton  Glacier   Mont 

Yellowstone  Lake' 

12 

10 
9  10 

10     9 
9  10 

10  11 
9  10 
9  10 
9     8 

10     9 

16  12 
9  10 

12  16 
10 

13  18 
10  10 

12 
10     9 
12  14 

9 

8 
10  10 
12     7 

6  7 

7  8 

7  6 

6  7 

8  7 

8  7 

9  7 

7  7 

8  7 
9 

8  9 
10     8 

12 

9  7 
8  10 

25 

9 
10  18 

14  10 

6  8 

8  9 

9  12 
9  10 

7  5 

8  5 

9  7 

8  8 

15  14 

9 

9  8 
17  15 

16 
13  11 
12  10 

34 

17 
20  28 

26  17 
11  15 

15  17 

16  18 
15  17 

15  12 

16  12 
18  14 
15  15 
23  21 

18 

17  17 

27  23 
28 

22  18 
20  20 

2.7 

2.4 
2.6 
2.0 
2.7 
2.2 
2.0 
2.8 
2.7 
2.3 
2.6 
2.5 
2.6 
2.1 
2.1 
2.6 
2.8 
2.3 
2.4 

Subspecies  lypica: 

29799  UC 
UC 
US 
SF 

154861  UC 
6495  Baker 

29800  UC 
Gr 

622063  US 

29797  UC 

29798  UC 
193573  UC 

29796  UC 

29801  UC 
283798  US 
431833  US 
983227  US 

US 

Italy                                     

St  John  River   Me 

Oswego,  N.  Y - 

Utioa,  N.  Y 

Near  Andover   N   J 

Glynn  County,  Ga          .... 

Detroit   Mich 

10 

8 

10 

19 

2.4 

Subspecies  discolor: 

51519  UC 
135408  UC 

91235  UC 
193455  UC 
115S0a  CI 

11552  CI 
205772  UC 

14 
9 

10 
9 
8 

10 

10 
9 

8 

15 
18 
19 
20 
16 
16 
16 

21 

28 
28 
29 
24 
24 
27 

2.0 
1.8 
2.3 
2.0 
2.2 
2.3 
2.0 

Sierra  La  Sal,  Utah* 

Durant,  Mont.' 

Gilmore   Idaho 

9 

« 

17 

25 

2.0 

98 


GENUS   ARTEMISIA. 
Table  6. — Variation  in  the  subspecies  of  Artemisia  vulgaris — Continued. 


Subspecies  heterophi/lUi: 

Edmonton,  Alberta' 

Wawawai,  Wash.' 

Klickitat  County,  Wash 

Mount  Puddo,  Wash 

Ketchum.  Idaho 

Grants  Pass,  Oreg 

Do 

Ormsby  County,  Nev 

Butte  County,  Calif 

Humboldt  County,  Calif 

Princeton,  Calif 

Palo  Alto,  Calif 

Verdugo  Cafion,  Calif 

Los  Angeles  County,  Calif. .  . . 
San  Bernardino  County,  Calif. 


Average . 


Subspecies  litoralis: 

Vancouver  Island 

Montesano,  Wash 

Whidbey  Island,  Wash. .  . 
Chuckanut  Bay,  Wash . . . 
Chehalis  County,  Wash.  . 

Umpqua  River,  Oreg 

Humboldt  County,  Calif. 
Scotia,  Calif 


Average. 


Subspecies  ludoviciana: 

Albany  County,  Wyo 

Rincon  Mountains,  Ariz. . . 

Marysvale,  Utah 

Klickitat  County,  Wash. . . 

Bluff  Lake,  Calif 

Poison  Spider  Creek,  Wyo. 
Carbon  County,  Wyo 


Average . 


Subspecies  gnaphalodea: 

Traverse  County,  Minn . 

Laramie,  Wyo 

Centennial,  Wyo 

Teton  Forest,  Wyo 

Gunnison,  Colo 

Elko  County,  Nev 

Modoc  County,  Calif .  .  . 

Oregon 

Wallowa  County,  Oreg. . 
Canon  County,  Idaho. . . 

Montana 

Sedan,  Mont 


Average. 


Subspecies  serrata: 

Taylor  Falls.  Minn 

Minnesota 

Glen  wood,  Minn 

Winona  County,  Minn. 
Northern   111 


Average . 


NY 

NY 

29795  UC 

Gr 

Gr 

172631  UC 

29687  UC 

135381  UC 

171429  UC 

169318  UC 

71769  UC 

75361  UC 

53973  UC 

149246  UC 

184750  UC 


NY 
NY 
76560  UC 
29802  UC 
173318  UC 
29683  UC 
204825  UC 
127815  UC 


146529  UC 
153811  UC 
159142  UC 
130200  UC 
149209  UC 


29783  UC 
67857  UC 
29758  UC 
46282  UC 
193540  UC 


No.  of 
bracts. 


10  10 
13  15 
10  11 
8  10 

8  10 

9  10 


No. 
of  ray- 
flowers. 


10  13 
10  11 
10  12 
10  12 
12  13 
10  11 


5  6 
7  10 

10  10 
7  7 
9  9 
9  10 
9  12 
7  8 
7     8 

6  10 

6  7 

7  8 


8  7 

6  7 

8  7 

9  7 


No. 
of  disk- 
flowers.' 


14  16 
11 
16 
20  15 
23  28 
7  6 
9  15 
11  11 
7  11 
23  23 
10 
11  12 
17  16 
14  15 
13  16 


20  25 
18 
22 

29  23 
32  37 
15  15 
15  23 
17  19 
13  17 

30  30 
15 

17  21 
25  24 

21  22 
21  24 


14 


21 


6  10 

7  8 
7  10 
9  12 
7  6 

12 
15 


13  18 
15  18 

14  17 

15  18 
14  12 

18 
22 


17 


5  5 
15  20 
13  17 

12  16 
19  20 

15  15 

16  17 

13  14 
21  21 
16  12 

8  8 
12  17 


10  11 

22  30 

23  27 

19  23 
28  29 

24  25 
24  29 

20  22 
28  29 
22  22 
14  15 
19  25 


24 


A.   VULGARIS. 
Table  6. — Variation  in  the  subspecies  of  Artemisia  vulgaris — Continued . 


Herbarium. 

No.  of 
bracts. 

No. 
of  ray- 
flowers. 

No. 
of  disk- 
flowers.' 

Total 
flowers.' 

Length 
of  diak- 
coroUa. 

Subspecies  mexicana: 

91175  UC 

135371  UC 
135375  UC 
135374  UC 
147496  UC 
135373  UC 

135372  UC 

11  13 

15 

9  10 

10  11 
9  11 

13 

11  13 

8     9 

8 

8     9 

7  8 
4     6 

8  9 
7     8 

15  18 
15 
9  11 
9  10 
4     7 

12  16 

13  13 

23  27 
23 
17  20 
16  18 
8  13 
20  25 
20  21 

mm. 
2.4 

Alvarez   Mex                    

Chihuahua   Mex 

2.2 
2.0 
1.7 
2.2 
2.5 

Jalisco   Mex 

Lincoln  County   N.  Mex 

11 

7 

11 

18 

2.2 

Subspecies  wrighti:" 

Black  Cafion   Colo  " 

34510  UC 
34515  UC 
34520  UC 
Oster.  2010 

11092  CI 

11093  CI 

11094  CI 
11122  CI 
11104  CI 

175395  UC 

NY 

NY 

91219  UC 

135407  UC 

11183  CI 

193609  UC 

Or 

7  9 
10  13 
12    8 
U  11 

8  10 

9  10 

10  9 
14     9 

9     11 

8  6 

9  9 

11  9 
9     7 
6     9 
8  10 
8     9 

14  13 

8  11 
11     9 

7  6 

8  8 
14  12 
16  13 
10     9 

9  7 

7  8 
6     6 

6  5 

8  10 

7  7 
4     5 

14  12 
6     7 
18  16 

14  10 

16  11 

8  6 

9  10 

18  21 

17  14 

15  14 

16  19 
10  12 

7  10 

7  6 

19  18 

8  4 
5     6 

16  16 
4     6 
16  18 

22  20 
27  20 
15  12 
17  18 

32  33 

33  27 
25  23 
25  26 
17  20 
13  16 
13  11 
27  28 
15  11 

9  11 
30  28 
10  13 

34  34 

2.2 
2.0 
2.0 
2.2 
2.1 
2.0 
2.2 
2.4 
2.1 
2.2 
2.3 
2.1 
2.0 
1.8 
2.0 
2.0 
1.9 

Pagosa  Spring  Colo        

Dale  Creek   Colo  " 

Do                                                                 .... 

San  Juan  Valley  Colo 

Southesistem  Utah         

Do 

Do 

Do 

Chihuahua" 

9 

8 

12 

21 

2.0 

•  Type  of  A.  herrioli  Rydberg,  minor  variation  27. 

•  Duplicate  type  of  A.  atomi/era  Piper,  minor  variation  4. 
'°  Includes  several  specimens  referable  to  minor  variation  8, 

A.  carrulhi  Wood. 
"  Minor  variation  5,  A.  bakeri  Greene. 
"  Type  of  A.  coloradensis  Osterhout,  minor  variation  9. 
"  Type  of  A.  pringlei  Greenman,  minor  variation  64. 


'  The  lower  numbers  sometimes  aYe  doubtless  due  to  loss 

of  flowers  in  pressing. 
'  Minor  variation  61,  same  as  A.  plati/ph]/lla  Rydberg. 

•  Type  of  A.  floccosa  Rydberg,  minor  variation  19. 

•  Type  of  subspecies  candicans  (Rydberg). 
'  Type  of  A.  aradlenta  Nelson,  minor  variation  25. 

•  Minor  variation  53,  A.  michauxiana  Besser. 
'  Minor  variation  30,  A.  incompta  Nuttall. 

ECOLOGY. 

The  subspecies  of  Artemisia  vulgaris  of  the  greatest  ecological  importance  are  hetero- 
phylla,  ludoviciana,  gnaphalodes,  mexicana,  and  wrighti.  These  are  all  typically  repre- 
sentative of  the  species  in  the  presence  of  rootstocks,  vigorous  growth,  and  late  blooming. 
As  a  consequence,  they  form  societies  in  the  late  summer  and  autumn  aspect  of  the  climax 
grassland,  and  persist  for  a  long  time  as  relicts  of  this  formation  in  cultivated  regions. 
The  similarity  in  their  behavior  is  perhaps  to  be  ascribed  to  their  close  relationship,  and 
may  explain  their  distribution,  as  they  appear  to  be  mutually  exclusive  to  a  high  degree. 
They  follow  the  grassland  into  the  savannahs  and  parks  of  the  foothill  and  montane 
zones,  reaching  the  maximum  elevation  at  about  9,000  feet  in  the  Rocky  Mountains. 

Artemisia  v.  gnaphalodes  is  most  characteristic  of  the  true  prairies,  but  is  also  an  impor- 
tant society  of  the  subclimax  and  mixed  prairies.  Like  its  relatives,  it  is  strongly  grega- 
rious, owing  to  its  stout  rootstocks,  and  the  society  often  has  the  appearance  of  many 
scattered  clans.  Ludoviciana  is  more  typical  of  the  foothill  portions  of  the  mixed  prairie 
and  runs  high  up  in  the  great  mountain  parks,  such  as  Estes  Park.  It  tolerates  consider- 
able shade,  and  is  an  important  feature  of  the  ground-cover  of  yellow-pine  woodland. 
The  rootstocks  are  less  stout  than  in  gnaphalodes,  and  the  plants  make  a  more  uniform 
society.  In  the  mixed  prairies  of  northern  New  Mexico  and  Arizona,  ludoviciana  is 
largely  replaced  by  mexicana  and  especially  wrighti,  with  essentially  the  same  ecological 


100  GENUS   ARTEMISIA. 

behavior.  Heterophylla  is  the  characteristic  form  in  the  bunch-grass  prairies  of  Cali- 
fornia and  Oregon,  where  it  makes  societies  like  those  of  gnaphalodes.  In  California 
especially  it  has  largely  disappeared  with  the  native  grasses,  and  is  now  found  chiefly 
in  the  low  savannah  formed  by  the  coast  sagebrush.  In  Washington  and  British  Colum- 
bia heterophylla  is  largely  replaced  by  tilesi,  which  takes  a  similar  role  in  the  grassland. 

In  addition  to  the  dominant  grasses  of  the  respective  associations,  these  forms  mix  and 
alternate  with  a  large  number  of  subdominant  herbs,  especially  the  asters,  goldenrods, 
sunflowers,  and  other  species  of  the  autumnal  aspect.  Gnaphalodes,  ludomciana,  or 
wrighti  is  frequently  associated  with  one  or  more  of  the  other  grassland  species  of  Arte- 
misia, namely,  dracunculus,  campestris,  and  frigida.  On  the  Pacific  Coast  heterophylla  is 
often  found  with  A.  calif ornica,  and  in  the  interior  with  A.  tridentata. 

As  indicators,  all  of  the  subspecies  considered  denote  the  climax  association  and  cli- 
mate, and  hence  are  valuable  in  reconstructing  grassland  that  has  disappeared.  This  is 
particularly  true  in  California,  where  the  deep-rooted  heterophylla  persists  long  after  the 
native  bunch-grasses  have  been  grazed  out.  In  general,  gnaphalodes  and  ludomciana 
indicate  greater  moisture,  as  they  are  most  abundant  in  the  moister  true  prairies  and  foot- 
hills respectively.  As  a  rule  they  are  not  good  indicators  of  overgrazing  and  other  dis- 
turbance, probably  owing  to  their  lack  of  mobility,  and  are  in  corresponding  contrast  to 
other  grassland  species,  such  as  A.  frigida  and  campestris. 

USES. 

This,  the  most  abundant  sagewort  in  western  North  America,  forms  an  important  part 
of  the  late  fall  and  winter  feed  for  all  classes  of  stock,  but  especially  for  sheep.  It  is 
variously  known  on  the  ranges  as  sage-weed,  white  sage,  and  mugwort.  The  taste  is  so 
pungent  that  it  is  scarcely  touched  until  after  frost,  but  late  in  the  season,  when  other  feed 
is  scarce,  it  is  quite  generally  eaten.  There  seems  to  be  no  preference  as  to  subspecies, 
since  all  of  the  common  ones,  particularly  discolor,  ludoviciana,  and  gnaphalodes,  are 
reported  upon  favorably.  It  seems,  therefore,  that  the  inclusive  name  of  Artemisia 
vulgaris,  or  sagewort,  is  the  only  one  with  which  the  grazing  experts  need  to  concern 
themselves  when  studying  the  value  of  these  plants. 

The  medicinal  properties  of  Artemisia  vulgaris  have  led  to  its  use  for  a  great  variety  of 
diseases.  This  has  been  largely  confined,  however,  to  domestic  practice,  the  plant  being 
scarcely  more  than  noticed  in  the  pharmacopoeias.  The  subspecies  typica  is  employed  in 
Europe  as  an  emmenagogue  and  for  epilepsy  and  colds.  In  California  subspecies  hetero- 
phylla is  used  by  the  Indians  as  a  remedy  for  colds,  headache,  fevers,  stomach  troubles, 
and  rheumatism.  The  methods  employed  are  described  by  Chesnut  (Contr.  U.  S. 
Nat.  Herb.  7:392,  1902).  In  France,  t3T)ical  vulgaris  has  been  worked  up  into  moxas, 
which  are  burned  for  purposes  of  cauterization.  Since  its  value  for  this  purpose  depends 
chiefly  upon  the  woolly  tomentum,  it  seems  that  some  of  the  more  heavily  tomentose 
American  subspecies,  such  as  candicans  or  gnaphalodes,  would  be  better  adapted  to  the 
purpose.  The  essential  oils  present  have  been  studied  by  Rabak  (Pharm.  Rev.  24:324, 
1906).  By  far  the  most  important  medical  use  of  the  plant  is  as  a  preventive  of  hay- 
fever  in  those  cases  which  are  caused  by  its  own  pollen.  Some  hay-fever  sufferers  are 
particularly  sensitive  to  the  pollen  of  this  plant,  as  is  indicated  by  skin-reaction  tests. 
Such  people  find  relief  by  taking  at  first  injections  of  very  dilute  pollen  solution  (about 
1 :  300,000)  and  gradually  increasing  the  strength  until  no  reaction  is  obtained.  This 
desensitization  enables  the  patient  to  pass  through  the  hay-fever  season  without  being 
subject  to  attacks,  assuming  that  he  is  not  suffering  from  the  effect  of  other  pollens  as 
well.  Preliminary  studies  indicate  that  the  pollen  of  the  different  subspecies  all  react 
alike.  Therefore,  in  testing  and  treating  hay-fever  cases,  the  specialist  need  pay  no 
attention  to  the  complicated  series  of  subspecies  and  minor  variations.  (See  further 
under  Atriplex  rosea,  p.  260.) 


A.    BIENNIS.  101 

12.  ARTEMISIA  BIENNIS  Willdenow,  Phytogr.  11,  1794.     Plate  10.     Biennial  Sagewort. 

An  annual  or  biennial  herb  from  a  taproot,  3  to  30  dm.  high,  nearly  inodorous;  stem 
simple  up  to  the  inflorescence,  erect,  striate,  glabrous,  often  tinged  with  red;  basal  leaves 
crowded,  widely  petioled,  5  to  15  cm.  long,  twice  pinnately  parted  or  divided  into  lan- 
ceolate sharply  toothed  or  cleft  divisions,  glabrous;  upper  leaves  mostly  larger,  once 
pinnately  parted  into  lanceolate  toothed  or  entire  divisions,  glabrous;  inflorescence  a 
compound  terminal  spike,  leafy  throughout,  10  to  50  cm.  long  by  1  to  2  cm.  broad  or 
rarely  the  lower  branches  elongated  and  the  inflorescence  thus  much  broader,  the  short 
branches  rigidly  ascending;  heads  heterogamous,  sessile,  crowded,  erect;  involucre 
hemispheric,  2  to  3  mm.  high,  slightly  broader;  bracts  8  to  14,  the  outer  ones  narrow 
and  green,  the  inner  ones  nearly  orbicular  and  scarious  except  along  the  green  midrib, 
all  glabrous;  ray-flowers  6  to  22  or  perhaps  more  numerous,  fertile,  corolla  oblique, 
slightly  under  1  mm.  long,  granular;  disk-flowers  15  to  40,  fertile,  corolla  campanulate, 
about  1  mm.  long,  3-  or  4-toothed,  granular;  style-branches  flat,  truncate;  achenes  ellip- 
soid, longitudinally  4-  or  5-nerved,  glabrous. 

Widely  distributed  in  North  America  except  in  the  southeast,  presumably  native  only 
from  the  northern  Rocky  Mountains  to  British  Columbia;  Nova  Scotia  to  New  Jersey, 
Missouri,  New  Mexico,  southern  California,  and  British  Columbia;  also  in  Kamchatka. 
Type  locality,  said  to  be  New  Zealand,  but  this  is  erroneous.  Collections:  Gloucester 
County,  New  Brunswick,  Blake  5639  (Or);  Longueil,  Quebec,  Brother  Vidorin  1054 
(US);  Naugatuck,  Connecticut,  August  30,  1903,  Bristol  (Or);  Canton,  New  York,  Phelps 
1016  (Gr);  Wayne  County,  Michigan,  September  16,  1916,  Chandler  (US);  Iowa  City, 
Iowa,  Somes  3923  (US) ;  Sheffield,  Missouri,  Bush  3300  (Gr,  NY,  US) ;  Castle  Rock,  Col- 
fax County,  New  Mexico,  August  28,  1913,  Wooton  (US);  Palo  Alto,  California,  Baker 
172  (DS,  Gr,  SF,  US);  Columbia  River,  in  Klickitat  County,  Washington,  September 
29,  1883,  Suksdorf  (US);  Beavermouth,  British  Columbia,  Shaw  1192  (Gr,  NY);  vicinity 
of  Glacier  Park  Station,  Montana,  Standley  17659  (US);  Traverse  County,  Minnesota, 
September,  1893,  Sheldon  (US);  Thomas  Lake,  Saskatchewan,  Macoun  and  Herriot 
72834  (NY). 

REIATIONSHIPS. 

The  close  connection  between  this  species  and  the  two  next  following  will  be  discussed 
under  A.  annua.  It  can  not  be  separated  from  annua  on  the  duration  of  the  root,  since 
this  is  variable  and  dependent  upon  local  conditions.  The  most  striking  difference  is 
the  character  of  the  inflorescence,  but  even  this  is  untrustworthy  in  reduced  forms  in 
which  the  small  heads  closely  simulate  those  of  annua.  The  heads,  however,  are  never 
nodding  and  never  distinctly  pedunculate,  and  the  achenes  are  larger  and  more  distinctly 
angled.  Mature  achenes  are  1  mm.  long,  while  those  of  related  species  are  only  0.5 
to  0.8  mm.  long.  Apparently  there  is  a  marked  difference  in  the  odor  of  the  crushed 
herbage,  but  this  requires  verification  by  field  examination  of  specimens  from  numerous 
widely  separated  localities.  There  is  little  to  indicate  which  of  these  two  species  is  the 
more  primitive,  but  the  larger  heads  with  more  numerous  flowers  seem  to  assign  this 
position  to  biennis.  A.  annua  then  becomes  a  derivative  that  has  undergone  a  reduction 
in  the  number  of  flowers  at  the  same  time  that  the  inflorescence  has  become  more  freely 
branched  and  the  heads  smaller  in  size. 

ECOLOGY  AND  USES. 

Artemisia  biennis  is  a  biennial  or  annual  with  a  taproot,  blooming  from  August  to 
December.  It  occasionally  forms  clans  in  the  grassland  formation,  but  it  is  typically 
a  ruderal,  growing  along  roadsides  and  in  waste  places.  In  these,  as  well  as  in  burns, 
it  sometimes  makes  a  pure  consocies,  but  it  is  usually  associated  with  other  weeds,  such 
as  Medicago  hispida,  Madia  saliva,  and  Centaurea  melitensis. 


102  GENUS   ARTEMISIA. 

Although  no  practical  value  attaches  to  this  plant,  it  is  of  economic  interest  because 
of  its  abundance  as  a  weed  in  certain  districts,  especially  in  the  Mississippi  Valley  from 
about  the  latitude  of  Missouri  northward.  Here  it  often  completely  occupies  fallow 
fields  and  other  waste  places,  reproducing  abundantly  from  seed.  It  is  easily  held  in 
check  by  cultivation  or  even  by  cutting,  if  the  tops  are  destroyed  before  the  seed  ripens, 
but  the  cutting  must  extend  over  at  least  two  seasons  since  the  root  is  often  of  biennial 
duration. 

Artemisia  biennis  is  objectionable  also  because  of  its  pollen,  which,  as  determined  by 
actual  tests,  is  one  of  the  causes  of  hay-fever  in  late  summer  and  autumn.  The  pollen 
is  spherical,  spiculate,  and  produced  in  great  abundance.  Its  use  in  pollen  therapy  is 
recommended  for  those  patients  who  give  a  positive  reaction  to  it  in  skin-tests. 

13.  ARTEMISIA  ANNUA  Linnaeus,  Sp.  PI.  847,  1753.    Plate  10.    Annual  Sagewort. 

An  annual  herb  from  a  taproot,  3  to  30  dm.  high,  very  sweet-scented;  stem  simple 
below,  erect  or  weak  and  fiexuous,  striate,  glabrous,  rarely  tinged  with  red ;  basal  leaves 
crowded,  petioled,  3  to  10  cm.  long,  once  or  twice  pinnately  parted  or  divided  into  lan- 
ceolate pinnatifid  segments,  glabrous;  upper  leaves  very  similar;  inflorescence  a  wide 
and  loose  terminal  panicle,  leafy  throughout,  10  to  50  cm.  long,  3  to  20  cm.  broad,  the 
very  slender  branches  (racemes)  widely  spreading  or  recurved;  heads  heterogamous, 
peduncled,  not  crowded,  often  nodding;  involucre  hemispheric,  1  to  1.5  mm.  high, 
slightly  broader;  bracts  8  to  14,  the  outer  ones  narrow  and  green,  the  inner  ones  broader 
and  scarious  except  along  the  green  midrib,  all  glabrous ;  ray-flowers  5  to  9,  fertile,  corolla 
oblique,  about  0.6  mm.  long,  granular;  disk-flowers  5  to  20,  probably  fertile,  corolla 
broadly  cylindric,  about  1  mm.  long,  toothed,  granular;  style-branches  flat,  truncate; 
achenes  narrowly  turbinate,  apparently  not  nerved,  glabrous. 

Native  of  Asia,  where  widely  distributed,  except  in  the  extreme  south,  and  of  eastern 
Europe,  naturalized  throughout  the  central  and  eastern  part  of  the  United  States,  to  a 
limited  extent  in  the  West,  and  in  eastern  Canada.  Type  locality,  Siberia.  Collections: 
Charlottetown,  Prince  Edward  Island,  Fernald  8236  (Gr) ;  Kingston,  Ontario,  September 
13,  1900,  Fowler  (Gr,  US) ;  Bridgeport,  Connecticut,  July  9,  1895,  Eames  (US);  Campbell 
County,  Virginia,  Fauntleroy  621  (US);  Cooke  County,  Tennessee,  Kearney  793  (NY, 
US);  Ralls  County,  Missouri,  September  13,  1913,  Davis  (SF);  Benton  County,  Arkansas, 
Plank  (NY);  Canton,  northern  New  York,  Phelps  1768  (Gr,  US);  Riverton,  Nebraska, 
Bates  4752  (Gr);  Los  Angeles,  California,  1908,  Arnold  (Gr). 

RELATIONSHIPS. 

This  is  one  of  three  species  of  the  section  Abrotanum  that  form  a  close  group  or  sub- 
section, the  other  two  being  biennis  and  klotzschiana.  They  are  all  annuals  or  at  the 
most  biennials  with  a  straight  taproot  and  a  terminal  inflorescence,  which  begins  well 
toward  the  base  of  the  strict,  erect  stem.  However,  some  doubt  as  to  the  close  relation- 
ship between  annua  and  the  other  two  was  introduced  by  J.  D.  Hooker  who,  in  his  Flora 
of  British  India,  reported  as  follows  (Fl.  Brit.  Ind.  3:323,  1881):  "Though  usually 
placed  in  the  section  Abrotanum,  I  find  the  ray-flowers  to  be  always  fertile  and  the  disk- 
flowers  sterile."  In  that  work  annua  was  transferred  to  the  section  Dracunculus. 
While  the  material  now  available  is  too  young  to  permit  of  a  definite  statement  as  to  the 
fertiUty  of  the  disk-flowers,  the  achenes  are  well  formed,  and  both  these  and  the  corollas 
are  almost  exactly  like  those  of  A.  biennis  at  the  same  stage  of  development,  except  that 
they  are  somewhat  smaller.  In  any  event,  the  two  are  so  close  in  all  other  essentials 
that  their  distribution  into  different  sections  seems  scarcely  advisable.  The  probable 
origin  from  A.  biennis  has  been  discussed  under  that  species. 


A.    ANNUA — A.    KLOTZSCHIANA.  103 

ECOLOGY  AND  USES. 

Artemisia  annua  is  an  annual  with  a  taproot,  which  occurs  in  America  as  a  naturalized 
weed  in  waste  places,  and  in  fallow  fields,  where  it  forms  a  consocies  of  the  secondary 
succession. 

It  is  probable  that  this  species  is  not  sufficiently  abundant  at  any  place  in  America 
to  be  of  much  interest  either  as  a  weed  or  as  a  cause  of  hay-fever.  It  may  be  held  in 
check  by  the  methods  described  under  A.  biennis,  but  the  process  may  be  simplified 
because  of  the  annual  duration  of  the  root. 

14.  ARTEMISIA  KLOTZSCHIANA  Besser,  Linnaea  15:107,  1841.    Plate  10. 

An  annual  herb  from  a  taproot,  5  to  10  dm.  (or  more?)  high,  the  odor  not  known; 
stem  simple  below,  strictly  erect,  striate,  conspicuously  canescent,  reddish  where  the 
tomentum  has  been  rubbed  off;  basal  leaves  crowded,  short-petioled,  less  than  2  cm. 
long,  bipinnately  divided  into  filiform  segments,  canescent;  upper  leaves  1  to  2  cm. 
long,  once  or  twice  pinnately  parted  or  divided  into  linear-filiform  segments,  gray  with 
a  dense  somewhat  villous  tomentum;  inflorescence  a  compound  terminal  spike  nearly 
as  long  as  the  whole  plant,  short-leafy  throughout,  20  to  50  cm.  (or  more?)  long,  about 
2  cm.  broad,  or  much  broader  when  composed  of  ascending  spike-like  branches;  heads 
heterogamous,  sessile  or  subsessile,  erect;  involucre  hemispheric,  2.5  to  3  mm.  high  and 
slightly  broader;  bracts  12  to  18,  all  elliptic,  green  beneath  the  canescent  tomentum 
save  for  a  narrow  white-scarious  border;  ray-flowers  50  to  70  (?),  fertile,  corolla  narrowed 
above,  less  than  1  mm.  long,  granular;  disk-flowers  6  to  12,  fertile,  corolla  campanulate, 
about  1  to  1.3  mm.  long,  4-  or  5-toothed,  granular;  style-branches  of  ray-flowers  acute, 
of  disk-flowers  truncate  at  the  penicillate  summit;  mature  achenes  not  seen. 

Mexico,  from  Coahuila  and  San  Luis  Potosi  to  Vera  Cruz  and  Hidalgo;  also  in  Ecuador. 
Type  locality,  plains  of  Perote,  Vera  Cruz.  Collections:  Saltillo,  Coahuila,  Palmer  87 
(Gr);  San  Luis  Potosi,  Schaffner  706  (NY,  US);  city  of  Zacatecas,  Palmer  784  (Gr); 
near  Zontecomate  Station,  Hidalgo,  Pringle  8918  (Gr,  NY,  UC,  US);  Pachuca,  Hidalgo, 
Purpus  1566  (NY,  UC). 

RELATIONSHIPS. 

There  is  little  doubt  that  this  species  is  closely  related  to  A.  biennis,  notwithstanding 
its  very  different  appearance  due  to  the  remarkably  dense  gray  pubescence.  The  leaves 
are  much  smaller  in  the  present  species,  the  involucral  bracts  are  narrower  and  less 
scarious,  and  the  achenes  are  slightly  smaller  and  probably  less  distinctly  angled.  It  is 
not  impossible  that  the  disk-achenes  both  in  klotzschiana  and  annua  are  partly  sterile, 
whereas  they  are  normally  all  fertile  in  biennis,  but  this  opinion  requires  more  material 
before  it  can  be  verified.  The  exceptionally  large  number  of  ray-flowers,  that  is,  54  to 
68  in  the  plants  examined,  is  unique,  but  the  number  will  doubtless  be  found  to  be  more 
variable  as  further  collections  are  studied. 

There  is  a  wide  gap  between  the  geographic  area  occupied  by  this  species  and  that  of 
A.  biennis.  It  is  not  surprising,  therefore,  that  a  number  of  minor  morphological  dif- 
ferences can  be  found,  as  noted  above,  and  that  there  are  no  intermediate  forms  as  to 
pubescence.  It  is  possible  that  klotzschiana  is  an  offshoot  from  A.  vulgaris  through 
subspecies  wrighti,  which  it  much  resembles  in  superficial  appearance,  but  from  which 
it  differs  in  floral  characters,  the  large  number  of  ray-flowers,  and  especially  in  the  very 
different  root-system. 

The  extension  of  range  of  this  species  southward  to  Ecuador  is  on  the  basis  of  a  single 
specimen  at  the  New  York  Botanical  Garden  collected  by  Rose.  Further  field  explora- 
tion will  be  necessary  to  determine  whether  it  is  a  native  so  far  south  or  whether  it  has 
been  introduced  from  Mexico. 


104  GENUS   AKTEMISIA. 

ECOLOGY  AND  USES. 
Artemisia  klotzschiana  is  an  annual  with  taproot,  which  forms  clans  in  the  desert 
plains  grassland  at  high  altitudes  in  Mexico.     So  far  as  known,  no  use  is  made  of  this 
species. 

15.  ARTEMISIA  BIGELOVI  Gray,  Pacif.  R.  R.  Rep.  4:110,  1857.     Plate  9.     Flat 
Sagebrush. 

A  low  shrub,  commonly  2  to  4  dm.  high,  the  odor  faint,  pleasant,  not  pungent;  stems 
many,  spreading  below,  the  numerous  flowering  branches  slender  and  erect,  the  bark 
apparently  sheathing  on  the  old  parts,  the  twigs  densely  silvery-canescent,  not  striate; 
principal  leaves  sessile  by  a  narrow  base  or  apparently  petioled,  linear-cuneate,  1  to  2 
cm.  long,  2  to  4  mm.  wide,  sharply  3-toothed  at  the  truncate  apex  or  many  entire,  silvery- 
canescent;  upper  leaves  linear-elliptic  or  linear-cuneate,  mostly  entire,  acute  or  slightly 
obtuse,  silvery-canescent;  inflorescence  an  elongated  narrow  panicle  with  short  recurved 
branches,  sometimes  nearly  simple  and  spike-like,  8  to  20  cm.  long,  1  to  4  cm.  broad; 
heads  heterogamous,  or  rarely  homogamous  on  the  same  plant  by  reduction  of  the  ray- 
flowers,  sessile,  several  in  each  short  recurved  cluster;  involucre  turbinate,  2.5  to  3.5  mm. 
high,  2  to  2.5  mm.  broad;  bracts  8  to  12,  the  outer  ones  ovate,  thick, and  only  half  as  long 
as  the  inner  ones,  these  oblong  and  obtuse,  all  densely  short-tomentose,  the  margins 
scarious;  ray-flower  usually  solitary,  sometimes  2,  or  wanting,  corolla  cylindric,  1  to  1.5 
mm.  long,  narrowed  above,  obscurely  toothed;  disk-flowers  1  to  3  (usually  2),  fertile, 
corolla  broad-funnelform,  5-toothed,  2  to  3  mm.  long,  glabrous;  style-branches  of 
ray-flowers  2-cleft,  exserted,  of  disk-flowers  2-cleft,  the  branches  erose-truncate,  included; 
achenes  of  both  ray  and  disk  ellipsoid,  about  5-ribbed,  glabrous. 

Southern  Rocky  Mountains,  from  southern  Colorado  and  southeastern  Utah  to 
northwestern  Texas  and  western  Arizona.  Type  locality,  rocks  and  canons  on  the 
Upper  Canadian,  Texas.  Collections:  Bluffs  near  Pueblo,  Colorado,  September,  1873, 
Greene  (Gr) ;  Soda  Springs  Ledge  and  Frank's  Ranch,  Cafion  City,  Colorado,  Brandegee 
996  (UC) ;  southeastern  Utah,  Rydberg  and  Garrett  9876  and  9891  (NY,  UC) ;  type  collec- 
tion, 1853-54,  Bigelow  (Gr,  NY  "Rocky  Dell,  September  18,  western  border  of  Texas," 
according  to  label  in  Torrey  Herb.) ;  White  Mountains,  New  Mexico,  Wooton  502  (NY) ; 
Burro  Mountains,  New  Mexico,  Rushy  232,  in  part  (UC) ;  near  Farmington,  northwestern 
New  Mexico,  Hall  III4I  (UC);  Navajo  Indian  Reservation,  Arizona,  Standley  7355 
(NY,  type  collection  of  A.  petrophila  Wooton  and  Standley,  minor  variation  1);  Billings, 
Arizona,  Jones  4571  (US);  Grand  Canon,  Arizona,  Hall  11187  (CI). 

SYNONYM. 

1.  Artemisia  petrophila  Wooton  and  Standley,  Contr.  U.  S.  Nat.  Herb.  16:193,  1913. — Described  as 
having  homogamous  heads,  but  in  the  type  specimens  the  flowers  are  too  immature  for  a  positive  determination 
of  this  point.  In  every  other  respect  the  specimens  are  exactly  like  A.  bigelovi,  which  apparently  was  over- 
looked when  the  original  diagnosis  was  prepared.  The  type  came  from  near  Farmington,  New  Mexico,  where 
typical  bigelovi  is  plentiful,  especially  on  the  low  hills  towards  the  south. 

RELATIONSHIPS. 

The  habit,  general  appearance  and  vegetative  characters  of  this  species  are  so  nearly 
those  of  A.  tridentata  that  it  is  often  so  labeled  in  herbaria,  but  the  presence  of  marginal 
flowers  plainly  different  from  those  of  the  disk  assign  it  on  technical  characters  to  another 
section  of  the  genus,  namely  Abrotanum.  The  total  number  of  flowers  in  the  head  is 
greatly  reduced.  The  number  of  ray-flowers  is  never  more  than  2,  usually  1,  and  some- 
times none.  This  last  condition,  if  constant,  would  assign  the  species  to  the  section 
Seriphidium,  but  in  no  case  has  a  plant  been  found  in  which  more  than  a  small  percentage 
of  the  heads  were  without  ray-flowers.  It  may  therefore  be  accepted  as  a  highly  modified 
member  of  Abrotanum,  although  not  approached  by  any  other  species  of  this  section. 


A.    BIGELOVI. 


105 


In  thus  temporarily  assigning  bigelovi  to  Abrotanum  the  possibility  of  its  representing 
the  starting  point  of  the  Seriphidia  should  be  considered.  The  similarity  to  A.  iridentata, 
of  this  section,  seems  to  be  more  than  accidental.  The  tridentate  character  of  the  leaves, 
for  example,  is  almost  identical  in  these  two  species  and  does  not  occur  in  any  other 
American  species.  The  southerly  distribution  of  bigelovi,  along  the  borders  of  the 
much  more  widespread  tridentata,  also  suggests  that  it  may  be  the  precursor  of  this 
species  and  hence  probably  of  all  of  the  American  Seriphidia.  If  this  conclusion  is 
correct,  then  this  section,  as  generally  accepted,  had  two  origins,  the  other  being  from 
Old  World  species.  This  polyphyletic  origin  would  account  for  the  fact  that  the  Ameri- 
can members  of  Seriphidium  have  little  in  common  with  the  Eurasian  members,  and 
the  wide  geographic  gap  between  these  two  groups  also  would  thus  be  explained.  Since 
such  a  hypothesis  necessitates  parallel  development  on  the  two  continents  in  only  one 
character,  namely,  the  suppression  of  the  ray-flowers,  there  is  no  serious  objection  to  its 
acceptance,  but,  on  the  other  hand,  there  is  no  immediate  need  of  breaking  the  section 
Seriphidiuvi  into  two  sections  until  this  point  can  be  better  substantiated  and  characters 
brought  forward  to  serve  for  their  differentiation.  This  is  impossible  at  the  present  time, 
because  of  the  want  of  a  thorough  knowledge  of  many  Old  World  species. 

The  variation  in  the  number  of  ray-flowers  and  of  disk-flowers  is  indicated  in  table  7. 
The  tabulation  also  brings  out  the  fact  that  there  is  but  slight  variation  in  any  of  the 
characters  enumerated.  This  constancy  and  apparent  absence  of  plasticity  is  noticeable 
also  in  the  habit  and  vegetative  characters,  and  tends  to  confirm  the  view  that  bigelovi 
is  an  ancient  form  which,  although  perhaps  once  serving  as  a  starting-point  for  the 
Seriphidium  stock,  at  least  as  to  American  species,  is  now  in  a  quiescent  condition. 


Table  7. — Variation  in  involueral  and  floral  characters  of  Artemisia  bigelovi. 


Height  of 
involucre. 


No.  of 
ray-flowers. 


South  Pueblo,  Colo 

Canon   City,  Colo 

Do 

Western  Texas  (type) .  .  .  . 
Near  Farmington,  N.  Mex 

Northwestern  N.  Mex 

Near  Farmington,  N.  Mex 
Painted  Desert,  Ariz 

Do 

Coconino  County,  Ariz .  .  . 

Chambers,  Ariz 

Chalcedony  Park,  Ariz 

Near  Flagstaff,  Ariz 

Grand  Caflon,  Ariz 


11172 
205782 
205784 


3.0 
2.5 
2.6 
2.6 
3.2 
3.5 
2.9 
2.8 


2  0 

0  1  0 

1 


2  2   1 

0  0  1111 

110  11 


12   12 

2  2  2  2  2 

2  2  2 

2 

2  2  2 

3  2  2  2  2 

2  2  2 
2  2 

1  1  2 
2  2  2   12  2 

2  2  2  2  2 

2  2   1 
2  0  111 


Artemisia  bigelovi  is  a  dwarf  shrub,  closely  resembling  low  forms  of  A.  iridentata 
produced  by  overgrazing  and  burning.  In  the  mixed  prairie  of  northern  New  Mexico 
and  Arizona  it  often  forms  a  dominant  society  similar  to  the  low  savannah  produced  by 
sagebrush  on  the  northern  Great  Plains.  Like  the  latter,  it  is  really  a  consocies  post- 
climax  to  the  dominant  grasses,  and  hence  is  most  abundant  in  the  subclimax  stage 
preceding  them.  It  is  itself  dominant  in  low  areas  and  on  rocky  ridges  where  it  is 
gradually  replaced  by  the  grasses  as  the  succession  advances.  It  is  especially  character- 
istic of  cedar  savannah,  owing  to  the  generally  rocky  soil.  It  is  regularly  associated 
with  Hilaria  jamesi,  Sporobolus  cryptandrus,  and  Bouteloua  gracilis,  but  gradually  disap- 


106  GENUS   ARTEMISIA. 

pears  as  the  grama  sod  becomes  close.  It  mixes  more  or  less  with  A.  tridentata,  Chryso- 
thamnus  nauseosus  junceus,  Atriplex  confertifoUa,  and  especially  Gutierrezia  sarothrae. 
This  species  is  an  indicator  of  somewhat  less  xerophytic  conditions,  particularly  in 
consequence  of  less  competition,  and  is  to  be  regarded  as  a  relict  in  the  drier  grassland 
areas.  It  doubtless  owes  its  form  largely  to  grazing,  and  overgrazing  of  the  grasses 
causes  it  to  persist  in  the  climax  where  it  would  otherwise  disappear. 


The  foliage  is  more  palatable  to  stock  than  that  of  the  common  sagebrush.  The 
taste  is  less  bitter,  the  odor  less  strong,  and  the  slender,  leafy  twigs  are  less  woody. 
It  is  browsed  in  preference  to  other  shrulas  in  the  regions  where  it  grows  and  is  reported 
by  grazing  examiners  as  "very  good."  Over  much  of  its  distributional  area,  however, 
the  plants  are  not  sufficiently  abundant  to  add  largely  to  the  value  of  the  range.  It  is  of 
greatest  importance  in  northern  Arizona  and  northern  New  Mexico. 

Section  II.  ABSINTHIUM. 
Phylogeny  of  the  Species. 
The  species  which  gives  its  name  to  this  section  occurs  in  America  only  as  an  introduc- 
tion and  is  not  directly  connected  with  the  others.  The  remaining  three  are  of  one  stock, 
and  apparently  stand  in  direct  relation  to  one  another.  The  ancestral  form  was  quite 
certainly  a  perennial  Siberian  or  at  least  Arctic  herb.  The  development  of  a  subshrubby 
habit  and  dissected  foliage  resulted  in  A.  frigida,  which  spread  out  over  Eurasia  in  a 
variety  of  forms  and  also  invaded  North  America,  occupying  large  areas  on  the  plains 
and  foothills  as  far  south  as  Texas  and  Arizona.  From  this  developed  scopulorum  and 
pattersoni,  which  came  to  occupy  the  higher  altitudes  in  the  mountains  of  western  North 
America,  where  they  are  now  widely  isolated  from  all  of  their  relatives  except  frigida. 
They  retained  the  herbaceous  habit,  but  the  inflorescence  was  so  narrowed  as  to  become 
scarcely  more  than  a  raceme.  A.  pattersoni  apparently  arose  directly  from  scopulorum 
in  response  to  more  intense  alpine  conditions.  A.  rupestris  does  not  occur  in  America, 
but  is  inserted  in  the  chart,  since  possibly  it  represents  the  ancestor  of  frigida.  It  is 
probable,  however,  that  evolution  has  developed  in  the  opposite  direction,  that  is, 
rupestris  arose  through  the  loss  of  pubescence.  The  detailed  statistics  and  other  data 
from  which  the  above  conclusions  have  been  drawn  are  given  in  the  paragraphs  on 
relationships  that  accompany  each  of  the  species  in  the  following  account. 

16.  ARTEMISIA  ABSINTHIUM  Linnaeus,  Sp.  PI.  848,  1753.    Plate  11.    Absinthe 
Sage  WORT. 

A  perennial  herb,  but  sometimes  slightly  woody  at  base,  4  to  10  dm.  high,  very  fragrant; 
stems  clustered,  simple  below,  erect,  striate,  thinly  cinereous  or  glabrate  and  then 
commonly  reddish;  basal  leaves  long-petioled,  rounded-ovate  in  outline,  3  to  5  cm.  long 
in  addition  to  the  petiole,  2  or  3  times  pinnately  parted  into  oblong  or  oblanceolate 
obtuse  often  toothed  lobes,  silky-canescent,  sometimes  less  so  on  the  upper  side;  upper 
leaves  with  fewer  lobes  and  these  mostly  lanceolate  and  acute,  those  of  the  inflorescence 
from  parted  to  merely  cleft  or  entire  and  sessile,  all  silky  like  the  lower;  inflorescence  a 
profuse  leafy  panicle  with  straight  ascending  branches,  15  to  40  cm.  long,  5  to  20  cm. 
broad,  occasionally  much  narrowed,  the  tips  of  the  branches  extending  beyond  the 
leaves;  heads  heterogamous,  short-peduncled,  nodding;  involucre  hemispheric,  2  to  3 
mm.  high,  3  to  4  mm.  broad;  bracts  12  to  18,  the  outer  linear,  the  inner  broadly  elliptic 
and  obtuse,  all  canescent,  but  the  inner  with  broad  scarious  margins;  receptacle  covered 
with  long  white  hairs;  ray-flowers  9  to  20,  fertile,  corolla  1.5  mm.  long,  obliquely  short- 


A.    ABSINTHIUM. 


107 


toothed;  disk-flowers  30  to  50,  fertile,  corolla  campanulate,  about  1.5  to  2  mm.  long, 
5-toothed,  glabrous;  style-branches  spreading,  those  of  the  disk-flowers  truncate  and 
penicillate  at  the  ends;  achenes  nearly  cylindric,  but  narrowed  at  base  and  shghtly 
rounded  to  the  summit,  smooth,  glabrous. 

Native  of  Europe,  thoroughly  established  as  an  introduced  wayside  plant  in  eastern 
Canada  and  northern  New  England;  less  common  from  North  Carolina  to  Utah,  eastern 
Washington  (where  spreading  rapidly),  central  Oregon,  and  British  Columbia.  Type 
locality,  Europe.     Collections:  Near  Topsail,  Conception  Bay,  Newfoundland,  Howe 


!     rupesfr/s     \ 
\      (Siberian)      I 


Glabrous. 
Old  World 


I  ip.pa/fcrsonA 

Heads  i-s, 
5-7  mm. broad; 
disk-fls.  jo-120 


Herbaceous; heads 
racemose  or  solitary 
Ivs.  silvery.  American 


FiQ.  14. — Phylogenetic  chart  of  the  species  of  Artemiiia  section  AfcsirUAtum. 


and  Lang  121  Ji.  (Gr,  NY);  Brome,  Quebec,  Pmse  1311  (Gr);  Plevna,  Ontario,  August  14, 
1^02,  Fowler  (Gr);  Veazie,  Maine,  July  31,  1891,  Fernald  (Gr);  Milford,  Connecticut, 
Williams  5539  (Gr);  Morristown,  New  York,  Phelps  1767  (Gr);  Brookings,  South 
Dakota,  September,  1893,  Thornber  (UC);  Yellow  Bay,  Montana,  Butler  470  (NY); 
Medicine  Hat,  Assiniboia,  Macoun  10980  (Gr) ;  Salem,  Oregon,  J.  C.  Nelson  2395  (Gr, 
US). 

RELATIONSHIPS. 
This  differs  from  the  native  members  of  its  section  in  the  much  more  robust  habit 
and  ample  foliage.  It  is  never  decidedly  woody  at  the  base,  as  is  usually  true  of  A. 
frigida,  and  the  profuse  leafy  panicle  at  once  distinguishes  it  from  A.  scopulorum. 
However,  in  technical  characters  it  is  very  close  to  both  of  these,  thus  lending  support 
to  the  view  that  the  section  Absinthium  is  a  natural  group,  even  though  its  members 
are  few  and  widely  separated  geographically.  Outside  of  the  members  of  its  own  section, 
it  is  most  nearly  like  the  native  A.  franserioides,  of  the  southern  Rocky  Mountains. 


108  GENUS   ARTEMISIA. 

ECOLOGY  AND  USES. 

The  ecology  of  this  species  as  a  native  plant  is  unknown;  in  this  country  it  is  a  ruderal, 
associated  for  the  most  part  with  other  roadside  weeds. 

This  herb,  now  commonly  known  as  wormwood,  was  much  used  by  the  ancients  for 
various  maladies  and  for  counteracting  witchcraft  and  necromancy.  It  is  still  grown  in 
Europe  and  to  some  extent  in  this  country  as  a  medicinal  plant.  An  infusion  prepared 
from  the  leaves  and  tops  is  useful  as  a  mild  tonic  when  taken  in  moderate  doses,  but  it  is 
very  powerful  when  administered  in  quantity.  It  was  formerly  used  also  as  an  anthel- 
mintic and  thus  acquired  its  common  name  of  wormwood.  A  dark-green  volatile  oil 
is  obtained  by  distillation  of  the  dry  tops.  This  oil  has  the  strong  odor  of  the  plant  and 
is  a  powerful  local  anaesthetic,  being  useful  when  applied  locally  for  rheumatic  pains  and 
in  the  form  of  a  liquor  as  a  narcotic  stimulant  in  cerebral  exhaustion.  It  has  been  found 
by  Charabot  and  Laloule  (Bull.  Soc.  Chim.  France  4:280-290,  1907)  that  this  oil  forms 
most  abundantly  just  before  the  flowering  period  and  that  it  is  more  plentiful  in  the 
leaves  than  in  the  stems.  These  investigators  suggest  that  it  is  used  in  completing  the 
ripening  of  the  seed.  No  oil  was  found  in  the  roots  until  after  the  period  of  flowering, 
when  its  relative  proportion  was  considerably  increased.  Salt  of  wormwood  is  the  ash 
left  after  burning  and  consists  chiefly  of  carbonate  of  potash.  The  well-known  absinthe, 
used  especially  in  France,  is  a  beverage  made  by  infusing  the  plant  in  alcohol.  In  some 
European  countries  the  leaves  are  used  in  place  of  hops  in  the  manufacture  of  beer. 

17.  ARTEMISIA  FRIGIDA  Willdenow.  Sp.  PI.  3:1838,  1804.     Plate  11.     Prairie 
Sagewort. 

A  perennial  herb  but  often  decidedly  woody  at  the  base  or  even  somewhat  shrubby, 
1  to  4  dm.  high,  very  fragrant;  stems  freely  branched  from  the  base,  decumbent  or 
spreading  below,  the  annual  branches  erect,  very  leafy,  not  striate,  cinereous  or  silky, 
the  old  bark  brown;  basal  leaves  crowded,  petiolate,  roundish  in  outline,  0.5  to  1  cm. 
long  beyond  the  petiole,  twice  ternately  or  quinately  dissected  into  linear  or  narrowly 
oblanceolate  acute  divisions  and  usually  a  pair  of  simple  or  3-parted  stipule-like  divisions 
at  base  of  petiole,  silvery-canescent ;  upper  leaves  like  the  lower,  but  less  dissected  and 
becoming  sessile ;  inflorescence  a  narrow  short-leafy  panicle  with  nearly  erect  racemif orm 
branches,  10  to  30  cm.  long,  1  to  10  cm.  broad,  or  much  reduced  and  raceme-like  in  dwarf 
forms  of  poor  soil;  heads  heterogamous,  sessile  or  short-peduncled,  nodding;  involucre 
hemispheric,  2  to  3  mm.  high,  4  to  5  mm.  broad;  bracts  11  to  18,  those  of  the  outer  series 
linear  and  herbaceous  (scarcely  shorter  than  the  inner),  the  others  lanceolate  to  ovate, 
all  densely  long-villous,  the  inner  with  broad  whitish  scarious  margins;  receptacle  densely 
villous;  ray-flowers  10  to  17,  fertile,  corolla  contracted  above,  about  1  mm.  long;  disk- 
flowers  25  to  50,  fertile,  corolla  funnelform,  1.5  to  2  mm.  long,  5-toothed,  glabrous 
or  granular-granuliferous  especially  on  the  tube;  style-branches  of  ray-flowers  obtuse, 
of  disk-flowers  truncate  and  fimbriate  at  the  ends;  achenes  subcylindric,  narrowed  at 
base,  truncate  or  slightly  rounded  at  summit,  scarcely  ribbed,  glabrous. 

On  high  plains  and  in  the  mountains,  Saskatchewan  to  Minnesota,  Kansas,  western 
Texas,  northwestern  Arizona,  Utah,  British  Columbia,  and  Alaska;  also  native  of  Siberia; 
introduced  in  Nova  Scotia,  eastern  Canada,  and  New  Jersey.  Type  locality,  Davuria, 
eastern  Siberia.  Collections:  Vicinity  of  Ottawa,  Ontario,  Rolland  6120  (Gr);  Fairville, 
New  Brunswick,  in  train  yards,  Fernald  2266  (Gr);  Custer,  Montana,  September  10, 
1890,  Blankinship  (UC);  Brookings  County,  South  Dakota,  August,  1892,  Thornber 
(Gr,  UC);  near  Minneapolis,  Minnesota,  August,  1889,  Sandberg  (UC,  US);  Laramie 
Hills,  Wyoming,  Nelson  5336  (UC);  Thomas  County,  central  Nebraska,  Rydberg  1733 
(Gr,  US);  Denver,  Colorado,  Eastwood  122  (Gr,  UC);  east  of  Eagle  Mountain,  Texas, 
November  1881,  Havard  (US);  near  Pecos,  San  Miguel  County,  New  Mexico,  Standby 


A.    FRIGIDA. 


109 


5212  (Gr,  NY);  Flagstaff,  Arizona,  September  5,  1894,  Tourney  (UC);  Table  Mountains, 
Nevada,  Purpus  6382  (UC) ;  eastern  Washington,  Griffiths  and  Cotton  362  (NY) ;  Thomp- 
son Falls,  Idaho,  Sandberg  981  (Gr,  NY) ;  vicinity  of  Banff,  Alberta,  McCalla  2019  (NY, 
US);  Fort  Chippewyan,  Athabasca,  Preble  187  (US);  Kamloops,  British  Columbia, 
July  28,  1890,  Macoun  (US) ;  Klondike  Valley,  near  Dawson,  Yukon,  Macoun  79016  (NY). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  A.  FRIGIDA  GMELiNiANA  Besser,  Hooker,  Fl.  Bor.  Am.  1:321,  1833. — Only  a  foliage  form  of  A.  frigida. 
Lower  leaves  long-petioled,  3-parted,  the  segments  5-parted,  lobes  linear,  acute,  the  middle  ones  short,  lowest 
lobes  stipule-like;  cauline  leaves  pinnatisected,  the  lower  segments  remote  from  the  upper.  Collected  on  the 
Saskatchewan. 

2.  A.  viRGATA  Richardson,  Franklin's  Journey,  App.  747,  1S23. — According  to  W.  J.  Hooker  (Fl.  Bor.  Am. 
1:321,  1833),  this  is  identical  with  No.  1  of  this  list. 

RELATIONSHIPS. 

Artemisia  frigida  is  most  nearly  approached  by  species  of  northern  Europe  and  Siberia. 
Since  it  is  most  plentiful  and  variable  in  northern  regions,  it  seems  quite  certainlj'-  to  be 
of  boreal  origin.  It  is  in  no  way  connected  with  Mexican  or  other  southern  forms. 
Several  Old  World  species  of  its  section  resemble  it  in  general  appearance,  but  differ  in 
such  details  as  having  pilose  or  even  lanate  corollas.  This  leaves  but  one  species  to 
which  it  can  be  directly  compared,  namely,  A.  rupestris  Linnaeus,  a  rather  common  plant 
from  Scandinavia  to  Siberia,  where  it  overlaps  the  range  of  frigida.  These  two  approach 
each  other  so  closely  in  habit  as  well  as  in  all  important  characters  that  they  might  almost 
be  taken  as  one  collective  species.     A.  rupestris  is  apparently  the  derivative,  since  in  it 

Table  8. — Variation  in  Artemisia  frigida  (a  stable  species). 


No. 
of  ray- 
flowers. 


No. 
of  disk- 
flowers. 


Length 
of  ray- 
corolla. 


Length 
of  disk- 
corolla. 


Near  Bosler,  Wyo.  (dwarf) . 

Golden,  Colo 

Palmer  Lake,  Colo 

Do 

Salida,  Colo 

East  Denver,  Colo 

Table  Mountains,  Nev 

Alaska 


CI 
CI 
CI 

UC 
205770  UC 

UC 
9120S  UC 
190648  UC 


2.0 
2.2 
2.1 
2  0 
2  0to2.5 
2.0 


13  16 

14  15 

14  13 

15  14 
13  15 
11-18 
15  14 

14 


9  12 
10  10 
13  16 
10  14 

8  12 

10-17 

10  11 

14 


33  29 
35  29 
25  29 
20-37 

34  29 


Average . 


the  inflorescence  has  undergone  reduction  to  a  nearly  or  quite  simple  raceme,  as  in  .4.. 
scopulorum,  and  the  leaves  have  a  more  decidedly  pinnate  arrangement  of  the  segments. 
The  foliage  is  almost  glabrous  and  therefore  green  instead  of  silvery-white  as  in  A. 
frigida.  It  apparently  has  larger  heads  with  more  numerous  flowers,  about  70  in  the 
specimens  at  hand,  but  this  may  not  be  constant.  While  these  characters  prevent  the 
merging  of  A.  frigida  into  this  older  species,  the  phylogenetic  connection  between  the 
two  is  established  with  reasonable  certainty.  The  nearest  American  representatives  are 
A.  scopuloruvi  and  A.  patter soni.  It  seems  probable  that  these  have  descended  directly 
from  A.  frigida,  as  shown  under  the  next  species. 

Variation  within  the  species  has  resulted  in  the  recognition  in  Asiatic  collections  of  a 
considerable  number  of  forms,  some  of  which  have  been  treated  as  species.  In  America, 
however,  there  is  a  remarkable  constancy  in  aU  essential  characters.  The  only  form 
indicated  as  in  any  way  divergent  is  the  one   listed  above   under  Minor   variations. 


110  GENUS   AETEMISIA. 

The  abundance  of  the  species  here  and  its  practically  continuous  distribution  over  the 
greater  part  of  its  range  accounts  perhaps  for  its  failure  to  develop  divergent ,  forms. 
Table  8  shows  that  the  extent  of  variation  in  characters  usually  employed  for  taxonomic 
segregation  is  not  great.  It  will  be  noted  also  that  the  variation  is  quite  as  extensive 
in  plants  growing  close  together  as  when  they  are  selected  from  widely  separated  locali- 
ties. This  is  seen  in  the  sixth  entry.where  the  figures  represent  the  extremes  of  8  plants, 
all  gathered  on  the  plains  at  East  Denver,  Colorado,  from  an  area  of  only  a  few  hectares. 
The  variation  here  is  about  as  great  as  between  the  other  collections  Usted,  showing  that 
there  is  no  tendency  towards  a  segregation  of  forms  in  the  territory  covered  by  this 
test. 

ECOLOGY. 
Artemisia  frigida  is  a  perennial  mat-forming  herb,  often  with  a  more  or  less  woody 
base.  It  is  one  of  the  most  characteristic  autumnal  societies  of  the  mixed  prairie, 
ranking  second  only  to  Gutierrezia  sarothrae.  Its  abundance  in  the  climax  is  partly  a 
consequence  of  grazing,  and  is  due  to  the  position  of  the  leaves  in  a  mat.  As  a  result 
it  is  one  of  the  chief  indicators  of  overgrazing  on  the  Great  Plains,  usually  mixing  with 
Gutierrezia  in  the  central  portion,  exceeding  it  in  the  northern  part,  and  falling  far 
below  it  in  abundance  in  the  south.  In  fallow  and  abandoned  fields  it  often  forms  a 
nearly  pure  consocies,  subclimax  to  the  grass  dominants.  In  its  behavior  to  disturbance 
it  is  similar  to  A.  campestris  and  A.  dracunculus,  with  which  it  is  often  associated. 

USES. 
The  prairie  sagewort  is  reported  by  stockmen  and  foresters  as  furnishing  an  important 
supply  of  forage  in  late  fall,  winter,  and  early  spring.  According  to  Macoun,  it  is  of 
great  economic  importance  as  a  forage  plant  in  Canada  (N.  Am.  Fauna  27:534,  1908), 
but  in  the  Plains  States,  where  there  is  a  better  supply  of  other  range  plants,  it  is  re- 
garded as  a  weed.  It  has  been  used  medicinally  to  some  extent  in  the  Rocky  Mountain 
States  under  the  names  of  Sierra  salvia.  Rocky  Mountain  sage,  and  wild  sage.  A  cold 
infusion  was  prepared  and  this  administered  as  a  diuretic  and  mild  cathartic,  but  it  is 
now  largely  replaced  by  other  drugs.  The  constituents  have  been  studied  by  Rabak 
(U.  S.  Dept.  Agr.  Bur.  Plant  Ind.  Bull.  235:21,  1912).  This  investigator  found  that 
the  herbage  contained  0.41  per  cent  of  a  very  fragrant  essential  oil  at  the  period  of 
flowering,  and  0.26  per  cent  after  blossoming.  Rabak  reports  that  the  oil  contains 
borneol  camphor  and  cineol  (eucalyptol),  both  of  which  have  valuable  antiseptic  qualities; 
also  some  fenchone  and  both  free  and  combined  acids.  He  makes  the  suggestion  that 
Artemisia  frigida  be  planted  for  medicinal  use  and  for  use  in  the  manufacture  of  cellu- 
loid; also  as  an  ingredient  for  medicinal  soaps  or  as  a  scenting  substance.  The  pollen, 
which  is  smooth  and  3-lobed,  is  the  cause  of  some  of  the  most  severe  cases  of  hay-fever 
in  the  districts  where  the  plant  is  abundant.  It  therefore  enters  into  pollen  therapy  as 
a  preventive  (see  A.  vulgaris,  p.  100). 

18.  ARTEMISIA  SCOPULORUM  Gray,  Proc.  Acad.  Phil.  1863:66,  1863.    Plate  12. 
Dwarf  Sagewort. 

A  perennial  herb  with  a  slenderly  branched  or  cespitose  rootstock,  1  to  3  dm.  high, 
mildly  odorous;  stems  several  or  numerous,  simple  up  to  the  inflorescence,  erect,  mod- 
erately leafy,  faintly  striate,  lightly  tomentulose  or  glabrate,  sometimes  becoming 
reddish;  basal  leaves  crowded,  petiolate,  2  to  3.5  cm.  long  including  the  petiole,  ovate 
to  obovate  in  outline,  mostly  twice  pinnately  parted  or  divided  into  narrowly  linear  or 
linear-oblanceolate  divisions,  about  1  mm.  wide,  silky-canescent ;  upper  leaves  much 
reduced,  less  parted,  those  of  the  inflorescence  often  simple,  silky  like  the  lower;  in- 
florescence (of  5  to  25  heads)    raceme-like,  congested  towards  the  summit,  2  to  10  cm. 


A.    SCOPULORUM.  Ill 

long,  0.5  to  1.5  cm.  broad;  heads  heterogamous,  subsessile  or  the  lower  long-peduncled, 
inclined  to  nod;  involucre  hemispheric,  about  4  mm.  high,  4  to  6  mm.  broad;  bracts  11 
to  18,  ovate  or  broadly  lanceolate,  somewhat  acute,  the  inner  ones  narrowed  at  base, 
villous,  with  greenish  narrow  backs  and  broad  blackish  scarious  margins;  receptacle 
copiously  villous;  ray-flowers  6  to  13,  fertile,  corolla  about  1.5  mm.  long,  funnelform, 
often  nearly  regular  and  4-  or  5-toothed;  disk-flowers  15  to  30,  fertile,  corolla  funnelform, 
2  to  2.5  mm.  long,  5-toothed,  long-villous  on  the  teeth  and  usually  also  on  the  throat; 
style-branches  of  ray-flowers  smooth  and  obtuse  at  apex,  of  disk-flowers  truncate  and 
penicillate  at  summit;  achenes  nearly  cylindric  but  slightly  narrowed  at  base,  mostly 
truncate  at  summit,  smooth  or  faintly  nerved,  not  pubescent. 

In  the  Rocky  Mountains  from  Montana  to  southern  Utah  and  New  Mexico;  most 
common  in  Colorado;  from  just  below  to  well  above  timber-line.  Type  locality,  Rocky 
Mountains,  Colorado.  Collections:  Spanish  Peaks,  Gallatin  County,  Montana,  July  20, 
1901,  Vogel  (Gr,  US);  La  Plata  Mines,  Wyoming,  E.  Nelson  5273  (UC);  type  collection 
1862,  Parry  (Gr) ;  Pike's  Peak,  Colorado,  at  edge  of  timber-line,  August  7, 1919,  Hall  R72, 
also  well  above  timber-line  A97  (CI);  mountains  about  headwaters  of  Clear  Creek, 
Colorado,  Patterson  72  (Gr,  NY,  UC,  US) ;  Sierra  Sangre  de  Cristo,  Colorado,  Brandegee 
788  (UC) ;  BuUion  Creek  near  Marysvale,  Utah,  Jones  5872  (NY) ;  La  Sal  Mountains, 
Utah,  at  3,000  to  3,200  m.  altitude,  Rydberg  and  Garrett  8964.  (NY,  normal  form  with 
elongated  inflorescence) ;  La  Sal  Mountains,  Utah,  at  3,300  to  3,600  m.  altitude,  Rydberg 
and  Garrett  8675  (NY,  UC,  a  dwarf  form  with  condensed  inflorescence  but  with  the  usual 
small  heads);  Pecos  Baldy,  New  Mexico,  Standley  4813  (NY,  US). 

RELATIONSHIPS. 

Artemisia  scopulorum  is  regarded  as  a  direct  descendant  of  A.  frigida,  which  has  been 
evolved  in  response  to  alpine  conditions.  The  style-branches  and  achenes  are  practically 
identical,  and  the  bracts  are  the  same  in  number  and  similar  in  shape,  while  the  measure- 
ments of  involucre  and  corolla  overlap,  as  do  the  numbers  of  ray-flowers  and  disk-flowers. 
The  leaves  are  distinctly  different,  and  there  are  considerable  differences  in  size,  habit, 
flower-cluster,  and  pubescence,  characters  all  readily  modified  by  the  environment. 
This  is  shown  by  the  form  of  A.  frigida  that  grows  on  cold  montane  plains  at  9,000  feet 
altitude,  which  is  dwarfed,  herbaceous,  less  silky,  and  with  a  raceme-like  inflorescence. 
It  proves  the  readiness  with  which  the  vegetative  features  of  this  plains  species  may  be 
changed  by  greater  moisture  and  cold,  and  suggests  the  actual  line  of  development  to 
scopulorum.  The  woody  base  of  frigida  is  clearly  an  adaptation  to  its  warmer  and 
drier  habitat,  and  it  disappears  at  higher  elevations.  Moreover,  while  the  two  species 
have  not  been  found  in  actual  contact,  it  is  probable  that  they  were  in  recent  times,  as 
frigida  ascends  to  3,000  meters  and  scopulorum  descends  to  3,400  meters.  Hence,  it 
appears  probable  that  the  boreal  A.  frigida  migrated  to  the  southward,  becoming  more 
woody  and  xeroid  on  the  plains,  but  retaining  its  herbaceous  character  in  the  subalpine 
region,  and  developing  into  the  dwarf  alpine  A.  scopulorum  on  the  high  peaks  of  Wyoming, 
Montana,  Colorado,  Utah,  and  New  Mexico. 

ECOLOGY  AND  USES. 

Artemisia  scopulorum  is  a  dwarf  alpine  perennial  with  short  rootstocks,  and  hence 
with  a  gregarious  habit.  It  may  occur  in  small  clans  in  new  areas,  but  it  is  usually  asso- 
ciated with  other  species,  such  as  Erigeron  uniflorus,  Antennaria  alpina,  Pedicularis 
parryi,  Arenaria  fendleri,  and  Haplopappus  pygmaeus,  in  a  mixed  society  of  the  alpine 
sedgeland  climax. 

No  uses  are  known  for  this  species,  and  none  are  to  be  expected  from  its  small  size  and 
alpine  habitat. 


112  GENUS   ARTEMISIA. 

19.  ARTEMISIA  PATTERSONI  Gray,  Syn.  Fl.  1':  453,  1886.    Plate  12.     Alpine 
Sagewort. 

A  perennial  herb  with  a  branched  or  cespitose  rootstock,  1  to  2  dm.  high,  mildly  odor- 
ous; stems  several,  unbranched,  erect,  moderately  leafy,  not  striate,  tomentulose  or 
glabrate,  not  turning  red;  basal  leaves  crowded,  petiolate,  2  to  4  cm.  long  including  the 
petiole,  obovate-oblong  or  spatulate  in  outline,  once  pinnately  parted  into  few  lobes,  1  to 
2  mm.  wide  or  only  trifid  from  the  summit,  silky-canescent;  upper  leaves  much  reduced, 
mostly  entire,  silky  like  the  lower;  inflorescence  (of  2  to  5  racemosely  arranged  heads  or 
reduced  to  a  single  terminal  head)  1  to  5  cm.  long,  about  1  to  1.5  cm.  broad;  heads  hetero- 
gamous,  subsessile  or  the  lower  long-peduncled,  mostly  horizontal  or  nodding;  involucre 
broadly  hemispheric,  about  5  mm.  high,  5  to  8  mm.  broad  (up  to  12  mm.  in  pressed 
specimens);  bracts  15  to  30,  ovate,  or  broadly  lanceolate,  acutish,  the  inner  ones  nar- 
rowed at  base,  villous,  with  greenish  backs  and  broad  blackish  scarious  margins;  recep- 
tacle copiously  villous;  ray-flowers  7  to  27,  fertile,  corolla  about  2  mm.  long,  funnelform, 
irregularly  toothed;  disk-flowers  32  to  120,  fertile,  corolla  funnelform,  2.5  to  3  mm.  long, 
5-toothed,  glabrous  or  rarely  sparsely  villous;  style-branches  of  ray-flowers  lanceolate, 
acutish,  of  disk-flowers  flat,  penicillate  at  the  truncate  apex;  achenes  nearly  cylindric, 
slightly  narrowed  at  base,  broad  at  summit,  smooth  or  faintly  nerved,  not  pubescent. 

High  mountains  of  Colorado  and  New  Mexico,  apparently  always  above  timber-line. 
Type  locality,  Rocky  Mountains  of  Colorado.  Collections:  Type  collection,  1862, 
Parry  (Gr,  type  of  A.  scopulorum  var.  monocephala  Gray) ;  about  the  headwaters  of  Clear 
Creek,  Gray's  Peak,  and  vicinity,  July  30,  1885,  Patterson  74  (Gr,  UC,  US) ;  Pike's  Peak, 
above  timber-Hne,  Hall  11079  (UC);  summit  of  Mount  Garfield  (Baldy),  Colorado, 
Clements  415  (DS,  Gr,  NY,  US);  Long's  Peak,  Colorado,  E.  L.  Johnston  689  (NY); 
Baldy,  New  Mexico,  August  14,  1910,  Wooton  (US). 

SYNONYMS. 

1.  Artemisia  monocephala  Heller,  Muhl.  1:118,  1905.    A.  patlersoni. 

2.  A.  SCOPULORUM  var.  MONOCEPHALAGray,  Proc.  Acad.  Phila.  for  1863:66,  1863.  The  original  name  for 
A.  pattersord,  as  indicated  later. 

RELATIONSHIPS. 

Artemisia  patter soni  appears  to  be  directly  derived  from  A.  scopulorum,  and  so  recently 
that  all  of  the  characters  overlap,with  the  exception  of  the  number  of  disk-flowers,  where 
they  meet.  This  is  further  indicated  by  the  fact  that  it  appears  to  be  known  from  but 
four  high  peaks— Gray's  Peak,  Long's  Peak,  and  Pike's  Peak  in  Colorado,  and  Mount 
Baldy,  New  Mexico.  While  the  two  species  are  now  often  found  together  on  these  peaks, 
the  smaller  plants,  reduced  leaves,  and  larger  heads  of  pattersoni  indicate  that  it  was 
developed  at  greater  altitudes  or  on  colder  slopes,  and  then  migrated  into  the  area  of 
scopulorum. 

This  species  is  very  similar  in  general  characters  to  A.  scopulorum,  so  much  so  that  it 
sometimes  has  been  taken  for  the  extreme  alpine  form  of  this  more  common  species. 
Both  were  first  described  by  Gray,  and  at  the  same  time.  Having  only  the  one-headed 
form  of  the  present  species,  this  authority  named  it  A.  scopulorum  var.  monocephala. 
Later,  however,  Patterson  called  Gray's  attention  to  differences  previously  overlooked 
and  the  latter  then  described  it  as  a  distinct  species,  A.  pattersoni  (Syn.  Fl.  P:453,  1886), 
which  was  characterized  as  follows: 

More  dwarf  and  white-tomontose,  but  sometimes  glabrate  in  age;  leaves  3-  to  5-parted  or  cleft,  or  uppermost 
entire;  heads  much  larger  and  broader,  solitary  or  2  to  5,  40-  to  50-flowered;  corollas  glabrous;  receptacle 
extremely  long-woolly.     (Syn.  Fl.  P:453,  1SS6.) 

This  is  not  merely  a  dwarf  of  scopulorum,  as  is  evident  from  the  occurrence  of  a  truly 
dwarf  form  of  the  latter,  in  which  the  essential  characters  of  pattersoni — cut  of  leaf,  large 
heads  with  numerous  flowers,  long   glabrous  corollas,  etc. — are  not  attained.      Such 


A.  PATTERSONI. 


113 


dwarfs  are  found  in  the  La  Sal  Mountains  of  Utah  (Rydberg  and  Garrett  8075)  and  on 
Gray's  Peak,  Colorado  {Shear  4997).  A.  patter soni  is  not  an  altitudinal  variant  of  scopu- 
lorum,  as  is  indicated  also  by  the  occurrence  of  both  within  a  few  feet  of  each  other 
without  the  presence  of  intergrading  forms.  Thus  on  Pike's  Peak,  at  a  point  about  1  km. 
south  of  Windy  Point,  but  still  well  above  timber-line,  one  may  find  small  areas  where 
only  scopulorum  grows,  while  only  4  meters  removed  there  are  areas  of  pure  pattersoni, 
the  intervening  space  being  occupied  by  other  plants. 

The  morphological  differences  between  these  two  species  are  indicated  in  table  9.  As 
there  shown,  they  exhibit  not  only  well-marked  divergent  tendencies  in  some  characters, 
but  in  one  of  these  there  is  also  an  absence  of  overlapping.  Thus,  the  number  of  disk- 
flowers  runs  from  10  to  31  for  scopulorum,  with  an  average  of  18,  while  pattersoni  has  32 
to  130,  with  an  average  of  85.  Further  examinations  might  exhibit  an  overlapping,  but 
on  the  other  hand,  the  lowest  counts  in  both  cases  are  probably  due  to  the  dropping  out  of 
some  of  the  flowers  before  the  counts  were  made.  Attention  is  also  called  to  universally 
pubescent  corollas  of  scopulorum  as  contrasted  with  the  almost  constantly  glabrous  ones 


Table  9. — Statistical  comparison  between  the  characters  of  Artemisia  scopulorum  and  A.  pattersoni. 


Herbarium. 


No.  of 
heads  per 


No.  of 
bracts. 


No.  of 

ray- 

flowere. 


No.  of 
disk- 
flowers. 


Total 
flowers. 


Corolla- 
lobes. 


Pike's  Peak,  Colo. 


Pike's  Peak,  Colo 

Seven  Lakes,  Colo 

Gray's  Peak,  Colo 

La  Plata  Mountains,  Colo 

Mineral  County,  Colo 

Vallecito,  N.  M 

Medicine  Bow  Mountains,  Wyo. . 

Big  Horn  Mountains,  Wyo 

Wind  River  Mountains,  Wyo 

Spanish  Peaks,  Mont 


Average . 


Do 

Baldy  Peak,  Colo. . 
Gray's  Peak,  Colo. 
Baldy,  N.  Mei.... 

Average 


11077  CI 
Do.... 
Do.... 
Do.... 
Do.... 

11078  CI 
Do.... 
Do.... 
Do.... 


Do. 


11080  CI 

858541  US 

488933  trS 

337427  US 

892761  US 

489803  US 

433965  US 

253360  US 

203786  US 

416310  us 


11076  CI 

Do.... 

Do.... 

Do ...  . 

Do.... 
11079  CI 

Do.... 

Do.... 

Do.... 


Do. 


Do 

CI 

A29  CI 

CI 

593762  US 

738710  us 


15 
13 

10  16 
5  10 

12  18 
15 
12 

7  9 
7  11 
9  15 


17  17 
14  10 
14  12 

14  12 
16  12 

15  14 
12  12 
12  12 

16  13 
12  14 
14  15 

18 


23  17 
13  10 
21  18 

18  16 

19  13 
17  17 
12  10 
21  17 
26  20 


32 
12  22 
15  24 
15  30 
29 
21 
15  24 
17  27 


8  15 
11  22 
11  27 
19 
20 
7  15 
7  16 


34  30 
23  19 
29  25 
29  22 
25  19 
23  24 
18  17 
27  23 

35  27 
27  28 
25  25 


Pubescent. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 


Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 
Pubescent. 
Glabrous. 


114 


GENUS  ARTEMISIA. 


of  pattersoni.  This  character,  however,  is  exceedingly  variable  in  other  species  of  Arte- 
misia. The  most  important  differences  not  brought  out  in  the  table  are  the  large  heads 
and  simply  cut  foliage  of  pattersoni  as  contrasted  with  the  smaller  heads  and  mostly 
dissected  foliage  of  scopulorum. 

ECOLOGY  AND  USES. 
Artemisia  pattersoni  closely  resembles  A.  scopulorum  in  life-form  and  ecological  rela- 
tions.    However,  it  never  forms  societies,  but  is  restricted  to  small  clans,  often  more  or 
less  mixed  with  A.  scopulorum.     No  uses  are  known  for  this  species. 

Section  III.     DRACUNCULUS. 
Phylogeny  of  the  Species. 

One  species  of  the  section  is  so  unUke  the  others  that  it  is  considered  as  representing  a 
very  early  divergence.  This  is  A.  spinescens.  Since  it  was  once  taken  as  the  type  of  the 
proposed  genus  Picrothamnus,  its  relationships  have  been  already  discussed  in  detail  (see 
p.  32).  The  remaining  four  species  are  readily  divisible  into  two  wholly  natural  pairs. 
A.  dracunculus  and  A.  campestris  are  presumably  of  Old  World  origin,  although  both  are 
now  abundantly  represented  in  America  by  a  number  of  subspecies.  Their  migration 
seems  to  have  been  by  a  route  across  or  around  the  North  Atlantic,  since  they  are  not 


Not  dwarfed;  in- 
florescence pan- 
iculate: disk-cor- 
olla under 
long 


Herbaceous 
species:  fis.usua 
more  than  is 


Dwarf;  inflores- 
cence spike-like 
disk-corolla 

5  mm.  long 


Shrubby  species; 
fis  usually  less 
fhan  15 


Not  sprnescent; 
achenes  and  corollas 
essentially  glabrous 


Spinescent ; 
chenes  and 
corollas  long-l 


Fio.  15. — Phylogenetic  chart  of  the  speciea  of  Artemiaia  section  Dracunculus. 


A.    DRACUNCULUS.  115 

represented  in  the  Northwest  nor  in  eastern  Asia.  As  contrasted  with  these,  filifolia  and 
pedatifida  are  restricted  to  America.  The  latter  shows  the  greatest  amount  of  modifica- 
tion and  possibly  was  derived  directly  from  the  former.  Both  exhibit  specialization  in 
their  shrubby  habit  and  in  the  reduction  of  the  number  of  flowers.  Perhaps  it  is  because 
of  these  special  adaptations  that  they  are  of  comparatively  limited  distribution. 

20.  ARTEMISIA  DRACUNCULUS  Linnaeus,  Sp.  PI.  849,  1753.    Plate  13.     Dragon 
Sagewort. 

A  perennial  herb  with  a  thick,  sometimes  nearly  woody  rootstock,  5  to  15  dm.  high, 
varying  from  strongly  odorous  to  inodorous;  stems  not  crowded,  simple  up  to  the  inflor- 
escence, erect,  striate,  either  pilose  and  glabrate  or  usually  glabrous,  commonly  tinged 
with  red ;  basal  and  lower  leaves  crowded  when  young  but  not  forming  tufts,  sessile  by  a 
narrow  base,  linear  to  oblong  or  somewhat  lanceolate,  acute,  3  to  8  cm.  long,  1  to  6  or 
10  mm.  wide,  mostly  entire,  occasionally  some  1-  to  3-cleft,  or  the  lowest  even  more 
divided,  usually  glabrous  but  silky-canescent  and  glabrate  in  some  forms;  upper  leaves 
only  slightly  reduced,  entire,  glabrous  or  pubescent;  inflorescence  a  leafy-bracted  panicle 
with  ascending  branches,  15  to  40  cm.  long,  3  to  12  cm.  broad;  heads  heterogamous,  ses- 
sile or  peduncled,  nodding;  involucre  hemispheric,  2  to  2.5  mm.  high,  2  to  4  mm.  broad; 
bracts  8  to  15,  elliptic  or  lanceolate,  mostly  obtuse,  the  outer  from  one-half  to  nearly 
as  long  as  the  inner,  glabrous  or  sparingly  pubescent,  yellowish  green  save  for  the  white- 
scarious  margins;  receptacle  naked;  ray-flowers  6  to  30,  fertile,  corolla  0.5  to  1  mm.  long, 
cleft  on  one  side,  glabrous;  disk-flowers  10  to  30,  sterile,  corolla  campanulate,  1.5  to  2 
mm.  long,  5-toothed,  glabrous;  style  of  disk-flowers  1  to  1.8  mm.  long,  the  branches  erect 
or  slightly  spreading,  penicillate  at  apex,  or  probably  the  branches  sometimes  com- 
pletely united;  achenes  ellipsoid,  not  ribbed,  glabrous,  those  of  the  disk-flowers  abortive. 

On  the  plains  and  in  the  mountains,  often  common,  Manitoba  to  Illinois,  Texas,  Chi- 
huahua, Arizona,  Lower  California,  and  British  Columbia,  also  in  central  Asia  and  Siberia 
and  less  common  in  middle  Europe. 

SUBSPECIES. 
Since  this  is  one  of  the  most  polymorphous  of  the  Artemisias,  an  extensive  series  of 
forms  might  be  worked  out.  The  following  key  provides  for  the  only  important  segre- 
gates thus  far  described  from  North  America.  Intermediate  forms  are  so  common  and 
the  characters  unite  in  so  many  combinations  that  it  is  often  impossible  to  place  speci- 
mens in  any  of  these  subspecies  with  certainty. 

Key  to  the  Subspecies  of  Artemisia  dracunculus. 

Heads   3   to   4    mm.    broad;  branches  of  inflorescence   not   drooping   at    ends;    leaves 

2  to  10  mm.  wide;  herbage  glabrous (a)  typica  (p.  115). 

Heads  2  to  3  mm.  broad;  branches  of  inflorescence  inclined  to  droop  at  ends  (except  per- 
haps in  glaxica);  leaves  1  to  3  mm.  wide  or  to  6  mm.  in  dracunculina;  herbage 
either  glabrous  or  pubescent. 

Panicle  comparatively  dense,  peduncles  mostly  2  mm.  or  less  long (6)  glaxica  (p.  116). 

Panicle  loose,  peduncles  2  to  6  mm.  long  and  very  slender.     Southwestern  United 
States  and  Mexico (c)  dTocunculina  (p.  116). 

20a.  Artemisia  dracunculus  typica. — Plant  glabrous  throughout,  aromatic;  leaves 
4  to  8  cm.  long,  2  to  10  mm.  wide,  rather  thick  and  firm;  branches  of  the  panicle  com- 
pact, erect  or  ascending  to  the  tip,  the  peduncles  stout  and  rarely  2  mm.  long;  involucre 
3  to  4  mm.  broad.  {A.  dracunculus  Linnaeus,  1.  c.)  The  common  form  in  western 
North  America,  cultivated  and  rarely  escaped  in  the  eastern  States,  common  also  in  the 
Old  World.  Wyoming  and  Colorado  to  Lower  California,  Washington,  Saskatchewan, 
and  Alberta.  Type  locality,  Siberia.  Collections :  Vicinity  of  Banff,  Alberta,  McCalla 
2018  (NY,  US);  Yellowstone  Lake,  Wyoming,  A.  and  E.  Nelson  6602  (DS,  Gr,  NY,  type 


116  GENUS   AHTEMISIA. 

collection  of  A.  aromatica  Nelson,  minor  variation  1);  Breckenridge,  Colorado,  Shear 
4564  (NY) ;  near  Marysvale,  Utah,  Jones  5942  (NY) ;  Chama,  northern  New  Mexico, 
Baker  631  (NY);  Cochise  County,  Arizona,  Eggleston  10815  (US);  San  Pedro  Martir, 
Lower  California,  Robertson  18  (UC) ;  Ballona,  coast  of  Los  Angeles  County,  California, 
Braunton  437  (UC) ;  San  Leandro,  middle  California,  Bolander  395  (NY) ;  Peavine  Moun- 
tain, western  Nevada,  Heller  10676  (DS,  Or,  NY,  US) ;  Wallowa  County,  Oregon,  Sheldon 
8635  (NY,  UC) ;  Peshastin,  Okanogan  County,  Washington,  Sandberg  and  Leiberg  829 
(Gr,  SF,  UC);  Canon  County,  Idaho,  Macbride  721  (Gr,  UC,  US). 

206.  Artemisia  dracunculus  glauca  (Pallas.) — Plant  silky  on  the  young  parts  and 
glabrate  or  glabrous  from  the  beginning  (minor  variation  4,  A.  dracunculoides  Pursh), 
inodorous;  leaves  3  to  8  cm.  long,  1  to  4  mm.  wide,  rather  thick  and  firm;  branches  of 
the  panicle  comparatively  dense,  inclined  to  droop  at  the  ends  because  of  the  slender 
branches,  the  peduncles  mostly  less  than  2  mm.  long;  involucre  2  to  3  mm.  broad.  Ap- 
parently there  are  Siberian  variations  with  wider  leaves  and  others  with  larger  heads. 
(A.  glauca  Pallas;  Willdenow,  Sp.  PI.  3:1831,  1804.)  Manitoba  to  Wisconsin,  Texas, 
Chihuahua,  New  Mexico,  and  British  Columbia;  also  in  Siberia.  Specimens  from  the 
San  Bernardino  Mountains  and  Catalina  Island,  Cahfornia,  sometimes  referred  here 
belong  to  subspecies  iypica.  Type  locality,  Siberia.  Collections,  mostly  of  the  glabrous 
form  and  therefore  of  minor  variation  4:  Brandon,  Manitoba,  Macoun  12257  (NY); 
Leeds,  North  Dakota,  September  6,  1901,  Lunnell  (Gr.);  Hennepin  County,  Minnesota, 
August,  1890,  Sandberg  (UC);  Des  Moines,  Iowa,  Pammell  1277  (Gr);  Fort  Collins,  Colo- 
rado, October  3,  1893,  Crandall  (NY);  southeastern  Utah,  Rydberg  and  Garrett  9133 
(NY,  only  a  few  of  the  branches  inclined  to  droop) ;  White  Mountains,  Lincoln  County, 
New  Mexico,  Wooton  306  (UC);  Texas,  Lindheimer  869  (Gr,  NY,  UC);  near  Colonia 
Garcia,  in  the  Sierra  Madre,  Chihuahua,  Townsend  and  Barber  295  (Gr,  UC) ;  Silver 
Canon,  Inyo  Range,  eastern  California,  Hall  10636  (UC);  sandy  banks  of  the  Colum- 
bia River,  west  Klickitat  County,  Washington,  Suksdorf  1609  (UC);  Eagle  Creek, 
Saskatchewan,  Macoun  and  Herriot  72828  (NY). 

20c.  Artemisia  dracunculus  dracunculina  (Watson).  Plant  softly  long-villous 
or  finely  canescent  on  all  the  young  parts,  in  age  glabrous,  or  occasionally  glabrous  from 
the  beginning,  inodorous;  leaves  3  to  8  cm.  long,  2  to  6  mm.  wide,  rather  thin  and  soft; 
branches  of  the  panicle  very  loose  and  open,  slender  but  scarcely  drooping  at  the  ends, 
the  slender  peduncles  (sometimes  drooping)  2  to  5  mm.  long;  involucre  2  to  2.5  mm.  broad. 
{A.  dracunculina  Watson,  Proc.  Am.  Acad.  23:279,  1888.)  Kansas,  Texas,  and  Chihua- 
hua to  New  Mexico  and  Arizona.  Type  locality,  at  the  base  of  cliffs  in  the  Sierra  Madre, 
Chihuahua.  Collections:  Riley  County,  Kansas,  Norton  298  (NY);  Corundos,  Texas, 
November,  1881,  Havard  (US);  type  collection,  under  calcareous  cliffs,  October  18,  1887, 
PringU  1309  (Gr,  NY,  UC,  US);  same  general  locality,  Pringle  1651  and  1652  (UC); 
Canon  de  San  Diego,  Chihuahua,  Hartman  778  (Gr,  NY,  US) ;  summit  of  San  Jose  Moun- 
tains, Sonora,  M earns  1677  (US);  among  rocks,  Sierra  County,  New  Mexico,  Metcalfe 
1444  (Gr,  NY,  SF,  US,  type  collection  of  A.  gracillima  Rydberg,  minor  variation  12); 
Organ  Mountains,  Dona  Ana  County,  New  Mexico,  September  28,  1902,  Wooton  (US, 
same  variation);  Bright  Angel  Trail,  Grand  Canon  of  the  Colorado  River,  Arizona 
Eastwood  3683   (SF). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Artemisia  aromatica  Nelson,  Bull.  Torr.  Club  27: 273, 1900.— A.  dracunculus  typica  (see  p.  117).  This 
was  included  m  A.  dTocunculoides  by  Gray,  in  the  Synoptical  Flora,  but  it  is  not  the  genuine  dracunculoides. 
Type  locality,  Yellowstone  Lake,  Wyoming. 

2.  A.  CERNUA  Nuttall,  Gen.  2: 143,  1818.— A  form  of  A.  dracunculus  glauca  with  shghtly  pubescent  herbage 
at  least  when  young,  and  with  branches  inclined  to  droop  at  the  ends.    Described  by  Rydberg  (N.  Am.  Fl. 


A.    DRACUNCULUS.  117 

34 :  252, 1916)  as  glabrous,  but  the  leaves  are  at  first  canescently  pubescent — according  to  the  original  description. 
A  piece  of  Nuttall's  type  at  the  Gray  Herbarium  is  puberulent  on  the  fohage  and  upper  portion  of  the  stem. 
Chiefly  of  the  lower  Mississippi  Valley.  Type  locality,  shrubby  savannahs  around  St.  Louis  and  on  the  banks 
of  the  Mississippi  and  Missouri  Rivers. 

3.  A.  DRAC0NCULINA  Watson,  Proc.  Am.  Acad.  23:279,  1888. — A.  dracunculns  dracunculina. 

4.  A.  DRACUNCULOIDES  PuTsh,  Fl.  Am.  Sept.  742,  1814. — A  form  of  A.  dracunculus  var.  glanca,  differing  from 
the  type  only  in  having  perfectly  glabrous  herbage.  Much  more  common  in  the  United  States  than  the  typical 
form.  The  name  draciinculoides  was  extended  by  Gray  (Syn.  Fl.  P :  369,  1884)  to  include  all  of  the  North  Ameri- 
can variations  of  A.  dracunculus  except  glauca,  the  one  to  which  it  is  most  closely  related.  In  fact,  typical 
dracunculoides  seems  no  more  than  an  ecologic  state  of  this.  Through  Gray's  treatment  the  commonest  form 
of  the  Rocky  Mountain  and  Pacific  States,  that  is,  subspecies  typica,  had  been  assumed  by  western  botanists 
to  be  typical  of  the  quite  different  dracunculoides,  until  Nelson  noted  the  discrepancy  and  named  it  A .  aromatica, 
apparently  overlooking  its  identity  with  the  European  A.  dracunculus.  The  type  locality  is  "  Upper  Louisiana," 
now  South  Dakota. 

5.  A.  DRACUNCULOIDES  BBEVIFOLIA  Torrey  and  Gray,  Fl.  N.  Am.  2:416,  1843. — A.  dracunculus  glauca. 
Somewhat  cinereous  or  glabrate.    Type  locality,  St.  Louis  to  the  Rocky  Mountains  and  the  Saskatchewan. 

6.  A.  DRACUNCULOIDES  INCANA  Torrey  and  Gray,  1.  c. — Probably  A.  dracunculus  glauca,  but  inflorescence 
unknown.    Type  locahty,  Jacques  River  [Quebec?]. 

7.  A.  DRACUNCULOIDES  TENUIFOLIA  Torrcy  and  Gray,  1.  c. — A.  dracunculus  glauca.  Canescent  or  glabrous; 
leaves  narrow,  elongated.    Type  locality,  St.  Louis  to  the  Rocky  Mountains  and  the  Saskatchewan. 

8.  A.  DRACUNCULOIDES  var.  WOLFI  Rydberg,  Bull.  Torr.  Club  32: 128,  1905. — A.  dracunculus  typica.  Type 
locality,  Twin  Lakes,  Colorado. 

9.  A.  DRACUNCULUS  GLAUCA  Besser,  Hooker,  Fl.  Bor.  Am.  1:326,  1833. — A.  dracunculus  subspecies  glauca. 

10.  A.  GLAUCA  Pallas,  Willdenow,  Sp.  PI.  3: 1831,  1804.— A.  dracunculus  glauca. 

11.  A.  GLAUCA  FASTIGIATA  Besser,  Bull.  Soc.  Hist.  Nat.  Mosc.  8:59,  1835. — .4.  dracunculus  glauca.  Branches 
fastigiate,  canescent  when  young.     Type  locahty,  plains  of  the  Saskatchewan. 

12.  A.  GRACiLLiMA  Rydberg,  N.  Am.  Fl.  34:253,  1916. — A.  dracunculus  dracuncidina,  but  with  the  pubes- 
cence canescent  rather  than  villous.     Type  locality,  1  mile  west  of  Hillsboro,  Sierra  County,  New  Mexico. 

13.  A.  NUTTALUANA  Besscr,  in  Hooker,  Fl.  Bor.  Am.  1 :  326,  1833. — From  the  description  this  seems  to  be  a 
glabrous,  short-leaved  form  of  A.  dracunculus  glauca.     Type  locality.  Red  River  of  the  North. 

RELATIONSHIPS. 

There  is  a  broad  gap  between  A .  dracunculus  and  its  nearest  relatives  when  the  species 
is  taken  in  the  broad  sense  as  here  defined.  Even  in  Europe,  where  its  origin  is  perhaps 
to  be  sought,  there  seems  to  be  no  species  with  which  it  is  in  very  close  alUance.  In 
America  it  is  most  closely  approached  by  A.  campestris,  as  will  be  indicated  under  that 
species. 

The  history  of  the  attempts  at  segregation  within  the  species,  both  here  and  in  the 
Old  World,  is  one  of  confusion.  This  is  due  in  part  to  a  lack  of  parallelism  in  the  varia- 
tion of  the  different  characters,  in  part  to  indefinite  characterization  of  the  segregates, 
and  in  part  to  a  disregard  of  forms  already  described.  For  about  a  century  nearly  all 
of  the  American  forms  have  passed  in  most  floras  as  A.  dracunculoides  Pursh.  The 
type  of  this,  the  common  form  in  the  Mississippi  Valley,  has  leaves  so  narrow  and  heads 
so  small  that  there  was  some  justification  in  separating  it  from  the  Old  World  A.  dracun- 
culus, but  the  form  which  is  by  far  the  most  abundant  in  all  of  the  western  States  is  so 
much  more  like  dracunculus  than  it  is  like  dracunculoides,  that  is,  subspecies  glauca  of 
the  present  treatment,  that  its  inclusion  in  the  latter  by  Gray  (Syn.  Fl.  P:369,  1884) 
has  resulted  in  much  confusion.  It  was  the  recognition  of  the  difference  between  the 
two  common  American  forms  that  led  Nelson  to  describe  the  broader-leaved,  larger- 
headed  one  as  A.  aromatica,  apparently  without  considering  the  Asiatic  type,  which  it 
practically  dupUcates  and  to  which  it  is  reduced  in  this  paper.  One  of  the  chief  charac- 
ters assigned  to  aromatica  by  Nelson  was  its  strong  odor  as  contrasted  with  dracunculoides. 
If  this  difference  was  constant,  which  seems  very  doubtful  from  field  observations,  it 
would  throw  aromatica  back  into  dracunculus,  for  the  only  tangible  character  given  by 
Gray  in  the  Synoptical  Flora  for  dracunculoides  is  that  it  is  "wanting  the  scent  and  taste 
of  A.  dracunculus."     The  odor  alone  is  quite  untrustworthy  as  is  indicated  by  the 


118 


GENUS   ARTEMISIA. 


experiments  of  Gmelin,  who  found  that  the  seeds  of  odorous  plants  produced  inodorous 
individuals  when  grown  in  the  botanical  garden  (according  to  Ledebour,  Fl.  Rossica 
2:563,  1846).  In  the  latest  account  of  our  species  (Rydberg,  N.  Am.  Fl.  34:244  to  285, 
1916),  aromatica  is  retained  as  a  species  and  separated  from  the  Old  World  dracunculus 
on  two  principal  characters:  (1)  the  outermost  bracts  are  said  to  be  almost  as  long  as  the 
innermost  instead  of  only  about  one-half  as  long;  (2)  the  flowers  are  given  as  30  to  100 
in  number  as  compared  with  20  to  40  in  dracunculus. 

The  supposed  difference  in  the  bracts  is  not  evident.  In  fact,  a  close  examination  of 
a  series  of  collections  indicates  the  same  relative  length  of  outer  and  inner  bracts  in 
American  and  European  material.  As  to  the  number  of  flowers,  the  figures  just  quoted 
show  a  sufficient  overlapping  to  suggest  the  doubtful  value  of  this  criterion  and  when  a 
large  series  is  examined  it  is  found  that  the  distinction  almost  completely  vanishes. 

Table  10. — Variation  in  the  sitbspeeies  of  Artemisia  dracunculus. 


Herbarium. 

No.  of 

involucral 

bracts. 

No.  of 

ray- 
flowers. 

No.  of 
disk- 
flowers. 

Total  no. 
of  flowers. 

Length  of 

corolla  of 

disk-flowers. 

Subspecies  typica: 

29745  UC 

51693  UC 

34508  UC 

175965  UC 

91256  UC 

65449  UC 

64995  UC 

205777  UC 

196572  UC 

CI 

170013  UC 

73885  UC 

205776  UC 

160228  UC 

NY 

549840  US 

200431  US 

NY 

NY 

Gr 

8  14 
8  10 

8  10 
14  15 

9  11 

12  12 

10  13 

11  12 

10  14 

11  12 

10  12 

11  14 

13  15 
n   13 

11  10 

12  11 
12  11 
10  11 

14  15 

8  13 

12  13 
18  20 

8  13 

13  15 

9  11 
9  11 

15  26 
17  14 
15  20 

21  26 

11  13 

12  26 
17   16 

14  17 

15  13 

13  11 
11   12 

9  12 

22  18 

16  16 
14  15 

19  20 

14  15 
18  10 

12  14 
27  29 
16  25 

13  20 
9  15 

25  23 
12   10 
12  23 

15  16 

11  14 

12  14 

11  14 

13  12 

12  11 

20  17 

24  29 

26  28 
37  40 
22  28 
31  25 

21  25 
36  40 

31  51 
30  34 
24  35 
46  49 

22  25 

24  49 

32  32 

25  31 

27  27 
24  25 
24  24 
21  23 
42  35 

2.0 
1.7 
2.0 
1.8 
1.6 
1.6 
1.5 
1.7 
1.7 
1.6 
1.8 
1.7 
1.8 
1.6 
1.7 
2.2 
2.0 
2.0 
2.0 
1.9 

Gunnison  Watershed   Colo 

Palomar  Mountains   Calif 

Waitsburg   Wash 

CafSon  County,  Idaho 

Tibet 

11 

14 

16 

30 

1.8 

Subspecies  glauca: 

67845  UC 
29743  UC 
172710  UC 
176480  UC 
112378  UC 
135380  UC 
147505  UC 
135379  UC 
130207  UC 
(12257)  NY 
Gr 
Gr 

9  11 

7  10 

8  10 

6  8 

10  11 

8  9 

7  9 

9  10 
12   12 

11  10 
11   12 

10  U 

8     9 
12  14 

8     9 
12  17 

8  9 
10  10 

9  9 
15  12 
12  12 
12  10 

8  10 
11 

9  10 
18  20 
10  14 

12  20 
10  11 

8  12 
6     8 
14  21 

13  16 
13  12 

18  20 
19 

17  19 
30  34 

18  23 

24  37 
18  20 
18  22 
15   17 
29  33 

25  28 
25  22 

1.7 

2.0 
2.1 
1.6 

1^5 
1.7 
2.6 
1.9 
1.8 
1.5 

Klickitat  County   Wash 

Siberia 

9 

10 

12 

22 

1.8 

Subspecies  dracunadina: 
tievi  Mexico 

NY 
SF 

91224  UC 

91225  UC 
29742  UC 

91226  UC 

8  10 

7  8 

8  8 
10  12 

8  10 

9  10 

12  10 

14  14 

8  10 

11  18 

12  15 

16  12 
9  16 

6     7 
10  17 

10  12 

11  13 

28  22 
18  27 

20  21 
18  27 

21  30 
23  28 

1.8 
1.6 
2.0 
1.8 
1.6 
1.7 

Sierra  Madre   Max. 

Chihuahua   Mex 

Cation  de  San  Diego,  Mex. 

9 

12 

'' 

23 

1.7 

A.    DRACUNCULUS. 


119 


Panicle  dense; 

peduncles 

2  mm.  or  less  long 


© 


Panicle  I 
peduncles 
im.  long 


Heads  2-3  mm.  broad, 
Inclined  to  droop; 
Iv3.  1  to  3  or  6  mm.  wide. 
Inodorous 


This  is  shown  in  table  10,  where  the  first  14  collections  under  subspecies  typica  are  of  the 
American,  or  "aromatica,"  type  and  the  last  6  of  the  Old  World  type.  The  latter  group 
includes  one  collection  from  California,  since  it  was  considered  by  Rydberg  as  genuine 
dracunculus,  introduced  into  America.  These  counts  show  that  the  number  of  flowers 
is  21  to  51  for  the  American  form,  with  an  average  of  32,  and  21  to  42  for  the  Old  World 
form,  with  an  average  of  27.  These  results  would  of  course  be  different  if  a  larger  series 
were  studied,  especially  as  regards  the  maximum  in  both  forms,  but  it  is  extremely 
unlikely  that  the  difference  between  the  averages  would  be  sufficient  to  indicate  even 
a  tendency  towards  a  separation.  The  fig- 
ures here  given  are  based  upon  counts  in 
normal,  well-formed  heads  selected  from 
about  the  same  relative  position  in  the  inflor- 
escence in  every  case.  In  this  connection  it 
may  be  suggested  that  the  low  number  some- 
times obtained  for  Old  World  material  may 
be  due  to  the  fact  that  specimens  from  across 
the  sea  are  usually  less  carefully  preserved 
than  those  from  this  country,  and  as  a  result 
of  this  and  of  frequent  handling  some  of  the 
flowers  have  fallen  out. 

Because  of  the  wide  hiatus  in  geographic 
distribution,  some  have  thought  that  char- 
acters should  be  found  upon  which  to  base 
a  taxonomic  separation  of  the  New  World 
plants  from  the  original  A.  dracunculus,  at 
least  varietally.  But  every  attempt  thus  far 
made  has  completely  failed.  The  leaves 
average  perhaps  a  little  narrower,  3  and  4 
mm.  being  common  widths,  but  leaves  up  to 
7  and  8  mm.  wide  are  not  rare.  In  many 
cases  exact  counterparts  of  European  or  Asi- 
atic plants  can  be  found  here.  The  inevi- 
table conclusion,  therefore,  is  that  the  most  common  and  widespread  form  in  western  North 
America  is  not  even  varietally  separable  from  the  Old  World  A.  dracunculus. 

Of  the  other  subspecies,  glauca,  as  now  restricted,  is  a  narrow-leaved,  small-headed 
plant  with  every  appearance  of  being  an  undernourished  or  competition  form.  Yet  its 
occurrence  on  this  continent  in  greatest  abundance  toward  the  east  of  the  range  of  typica 
indicates  that  its  characters  may  be  somewhat  permanently  fixed.  It  is  here  made  to 
include  A.  dracunculoides  Pursh.  This  is  in  agreement  with  Gray's  treatment  (Syn.  Fl. 
P:369,  1884,  etc.),  except  that  this  author  did  not  use  the  earlier  name  and  extended 
the  concept  to  include  all  of  the  American  plants  of  subspecies  typica.  The  only  differ- 
ence between  glauca  and  dracunculoides  is  the  loose  pubescence  on  the  young  parts  of  the 
former,  and  this  is  variable  in  amount  and  in  persistence.  Geographic  distribution  offers 
no  aid  here,  since  both  forms  occur  in  the  northern  United  States.  Even  after  the  most 
refined  segregation,  such  as  that  illustrated  in  the  North  American  Flora,  it  is  necessary 
to  admit  the  same  form,  in  this  case  glauca,  both  in  Siberia  and  in  central  North  America, 
although  no  variety  of  A.  dracunculus  is  known  from  Alaska  or  other  intervening  terri- 
tory, a  distance  of  over  4,000  km.  The  subspecies  dracunculina  is  also  pubescent  when 
young,  but  is  very  different  from  all  of  the  others  in  its  thin  foUage,  very  open  inflores- 
cence, and  delicate,  elongated  peduncles.  These  characters  do  not  vary  in  unison,  as  is 
evidenced  by  collections  with  the  whole  habit,  inflorescence,  etc.,  of  this  subspecies,  but 


120  GENUS   ARTEMISIA. 

perfectly  glabrous  even  on  the  young  branches  (Chihuahua,  Lumholtz  778).  The  open 
panicle  with  elongated  peduncles  is  generally  found  in  plants  from  the  Southwest,  but 
villous  shoots  are  present  only  in  the  type  material.  Moreover,  open  panicles  and  long 
peduncles  (2  to  6  mm.)  are  found  in  northern  material  {Pammel  1277),  while  open  panicles 
are  not  at  all  infrequent  in  subspecies  typica  and  glauca.  Finally,  Mexican  material 
(Pringle  304)  may  show  open  panicles  and  short  peduncles.  It  is  therefore  evident  that 
dracunculina  can  not  be  accorded  specific  rank,  although  it  may  be  accepted  as  a  south- 
western subspecies  based  chiefly  upon  the  form  of  the  inflorescence,  at  the  same  time 
admitting  that  similar  inflorescences  sometimes  occur  in  other  forms. 

ECOLOGY. 
Artemisia  dracunculus  is  a  perennial  herb  with  a  stout  rootstock,  blooming  in  late 
summer  and  autumn,  as  do  practically  all  the  species.  It  is  a  typical  society  of  the  grass- 
land formation  during  late  summer  and  autumn,  but  it  is  much  more  abundant  toward  the 
north  and  in  the  foothill  and  montane  regions.  It  is  most  characteristic  of  the  true  and 
mixed  prairies,  but  is  also  important  in  the  bunch-grass  and  subclimax  ones,  though  rare 
or  lacking  in  the  desert  plains.  While  it  increases  somewhat  under  grazing,  it  is  eaten  in 
sufficient  quantity  to  prevent  its  becoming  a  particular  indicator  of  overgrazing.  It 
sometimes  indicates  disturbance  of  the  soil,  but  is  much  less  frequent  in  this  role  than 
either  A.  campestris  or  A.  frigida.  It  is  often  associated  with  one  or  both  of  these,  and 
also  with  A.  v.  gnaphalodes. 

USES. 

This  species  is  extensively  browsed  by  sheep  after  frost,  especially  in  the  western 
mountains.  Although  the  foliage  is  too  scant  to  give  it  a  high  value  as  compared  with 
some  of  the  sagebrushes,  the  dragon  sagewort,  or  smooth  sageweed,  as  it  is  sometimes 
called  on  the  range,  is  one  of  the  principal  forage  weeds  for  sheep  in  late  autumn  and 
winter. 

The  plant  is  cultivated  to  some  extent  in  Europe  under  the  name  of  tarragon,  or  estra- 
gon,  and  its  leaves  are  there  used  for  seasoning  salads  and  cooked  dishes.  Presumably 
only  the  aromatic  forms  are  employed  for  this  purpose.  The  leaves  are  used  in  the  fresh 
state,  or  they  may  be  cut  and  dried  in  the  autumn  for  use  afterwards.  It  is  also  utilized 
in  the  manufacture  of  a  variety  of  vinegar  known  as  estragonessig.  The  plants  are  easily 
grown  from  divisions  of  the  root  or  from  cuttings  and  do  best  in  warm,  rather  dry  situa- 
tions. In  some  parts  of  California,  especially  in  the  Tehachapi  region,  the  plant  is 
known  locally  as  Indian  hair  tonic  and  is  said  to  be  used  to  stimulate  the  growth  of  the 
hair.  The  pollen,  which  is  smooth  and  3-lobed,  sometimes  causes  severe  cases  of  hay- 
fever  in  western  North  America.  Its  importance  as  a  causative  factor  is  not  so  great 
as  that  of  certain  other  species,  such  as  vulgaris  and  tridentata,  chiefly  because  it  seldom 
occurs  in  quantity  near  cities. 

21.  ARTEMISIA  CAMPESTRIS  Linnaeus,  Sp.  PI.  846,  1753.     Plates  14.  15.     Field 
Sagewort. 

A  biennial  or  perennial  herb,  1  to  6  dm.  high,  scarcely  odorous;  stems  usually  several, 
or  solitary  in  the  short-lived  forms,  erect  or  ascending,  often  from  a  decumbent  base, 
striate,  glabrous  or  slightly  pubescent  (rather  densely  villous  in  one  variety), more  or  less 
tinged  with  red;  basal  leaves  crowded,  petioled,  2  to  10  cm.  long  including  the  petiole, 
0.7  to  4  cm.  wide,  2-  to  3-pinnately  or  only  1-  to  2-ternately  divided  into  linear  or  linear- 
filiform  (rarely  linear-oblanceolate)  divisions,  these  rarely  more  than  1  mm.  wide, 
appressed  silky  or  villous  to  glabrous;  upper  leaves  smaller,  once  or  twice  divided  into  3 
to  7  lobes,  the  uppermost  often  ternate  or  simple,  densely  pubescent  to  nearly  glabrous; 
inflorescence  an  elongated  panicle  with  raceme-like  or  spike-like  branches,  these  leafy 


A.    CAMPESTRIS.  121 

below,  or  reduced  in  northern  and  high-mountain  forms  to  a  nearly  simple  spike,  5  to  50 
cm.  long,  1  to  15  cm.  broad;  heads  heterogamous,  sessile  or  short-peduncled,  erect  or 
nodding;  involucre  hemispheric,  2  to  4  mm.  high,  about  as  broad;  bracts  8  to  20,  round- 
elliptic,  obtuse  or  subacute,  light  brown  or  yellowish  green  with  a  brown  medial  line, 
scarious-margined,  densely  villous  to  glabrous;  receptacle  naked;  ray-flowers  5  to  20, 
fertile,  corolla  1  to  1.5  mm.  long,  narrowed  above;  disk-flowers  6  to  30  or  perhaps  40, 
sterile,  corolla  campanulate,  1.5  to  3  mm.  long,  regularly  5-toothed,  yellowish- white  or 
often  purplish  above,  glabrous  or  the  teeth  pubescent;  style  of  disk-flowers  1.5  to  3  mm. 
long,  either  undivided  and  erose  around  the  cup-shaped  summit  or  slightly  cleft  into  more 
or  less  spreading  branches;  achenes  subcylindric,  glabrous,  those  of  the  disk-flowers 
abortive. 

On  the  plains  and  in  the  mountains  almost  throughout  North  America  except  in  the 
desert  districts:  Greenland,  Hudson  Bay,  and  the  Atlantic  seaboard  to  Florida,  Texas, 
New  Mexico,  California  (along  the  northern  coast  only),  Oregon,  and  Alaska;  also  in  Asia, 
Europe,  and  northern  Africa. 

SUBSPECIES. 

No  less  than  17  American  forms  of  this  species  have  been  segregated  by  various 
botanists  and  dignified  with  specific  rank;  13  are  recognized  in  the  North  American  Flora. 
Some  of  these  segregates  are  strikingly  unlike  in  appearance,  yet  all  are  held  in  one  natural 
group  by  a  remarkable  uniformity  in  all  essential  characters.  The  varietal  differences 
are  chiefly  those  of  duration  (with  its  resulting  differences  in  branching),  number  of 
flowers  (with  differences  in  the  size  and  shape  of  the  head),  and  nature  or  amount  of  the 
pubescence.  For  present  purposes  it  seems  necessary  to  recognize  but  6  of  the  variations, 
and  these  are  here  given  subspecific  rank.  Other  segregates  are  minor  variations  of 
these. 

Key  to  the  Siibspeeies  of  Artemisia  campestria. 

Involucre  mostly  2  to  3  or  rarely  3.5  mm.  high,  2  to  3.5  mm.  broad;  root  either  biennial 
or  perennial. 
Plant  perennial;  stems  usually  several. 

Inflorescence  open-paniculate;  heads  nearly  ovoid;  leaves  moderately  pubescent, 

glabrate (a)  typica  (p.  121). 

Inflorescence  densely  paniculate;  heads  nearly  hemispheric  at  maturity;  leaves 

densely  and  permanently  pubescent (6)  pacifica  (p.  122). 

Plant  biennial;  stem  usually  single (c)   caudata  (p.  122). 

Involucre  3  to  4  mm.  high,  3.5  to  5  mm.  broad;  root  strictly  perennial. 
Pubescence  when  present  appressed  and  silky. 

Involucre  glabrous  or  nearly  so;  divisions  of  leaves  linear  or  very  narrowly  ob- 

lanceolate (d)  borealis  (p.  122). 

Involucre  densely  villous;  divisions  of  leaves  often  hnear-oblanceolate (e)   spithamaea  (p.  123). 

I^ibescence  loosely  silky-villous,  very  dense  and  extending  to  all  parts.     Pacific  coast,  if)   pycnocephala  (p.  123). 

21a.  Artemisia  campestris  typica. — Root  perennial;  stems  usually  several,  3  to  5 
dm.  high,  very  leafy  at  base,  sparsely  leafy  above;  leaves  mostly  twice  pinnately  divided 
into  linear  or  linear-filiform  divisions  about  0.5  mm.  wide,  the  upper  less  divided  or  entire, 
all  pubescent  at  first  but  often  glabrate;  inflorescence  openly  paniculate,  3  to  15  cm. 
broad,  the  branches  few  and  spreading;  heads  nodding,  ovoid  when  young,  expanding 
in  age  to  hemispheric;  involucre  2  to  3  mm.  high,  about  2.5  mm.  broad,  glabrous;  disk- 
flowers  5  to  12,  the  corolla  1.8  to  2.5  mm.  long.  {A.  campestris  Linnaeus,  Sp.  PI.  846, 
1873.)  Abundant  on  the  plains  of  Europe  and  western  Asia;  occasionally  found  on  the 
Atlantic  Coast  of  North  America,  where  perhaps  introduced.  Type  locaUty,  Europe. 
Collections:  Marthas  Vineyard,  Massachusetts,  August,  1888,  Burgess  (no  roots  but 
inflorescence  open);  Naugatuck,  Waterbury,  Connecticut,  July  14,  1903,  Bristol  (Gr); 
Aiken,  South  Carolina,  Eggleston  5063  (NY,  probably  this  subspecies,  although  without 
root). 


122  GENUS   ARTEMISIA. 

216.  Artemisia  campestris  pacifica  (Nuttall). — Root  perennial;  stems  several  or 
numerous,  4  to  6  dm.  high,  erect  from  a  spreading  base,  densely  leafy  below,  moderately 
leafy  up  to  the  inflorescence;  leaves  twice  pinnately  divided  into  narrowly  linear  divisions 
about  1  mm.  wide,  canescent  or  silky  pubescent,  seldom  if  ever  glabrate;  inflorescence 
an  elongated  panicle  of  numerous  closely  ascending  branches,  3  to  12  cm.  broad  or 
occasionally  narrowed  to  1  cm.;  heads  subsessile,  horizontal  or  erect,  hemispheric; 
involucre  2  to  3  mm.  high,  about  2.5  mm.  broad,  glabrous  or  sparingly  short-hairy, 
greenish;  disk-flowers  10  to  25,  the  corolla  1.8  to  2.5  mm.  long.  {A.  pacifica  Nuttall, 
Trans.  Am.  Phil.  Soc.  II,  7:401,  1841.)  The  common  form  in  western  United  States: 
South  Dakota  and  western  Nebraska  to  New  Mexico,  Arizona,  Oregon,  Yukon,  and 
Saskatchewan.  Type  locality,  shores  of  the  Pacific  at  the  outlet  of  the  Oregon  (Columbia 
River),  in  sandy  places.  Collections:  Brookings,  South  Dakota,  September,  1894, 
Thornber  (UC) ;  Laramie,  Wyoming,  Nelson  7983  (Or,  NY,  UC,  as  A.  camporum  Rydberg, 
minor  variation  7);Kiowa  Valley,  western  Nebraska,  Rydberg  203  (NY,  same  variation); 
Ruxton  Dell,  Pikes  Peak,  Colorado,  Clements  156  (DS,  Gr,  NY,  US,  same  variation); 
La  Sal  Mountains,  Utah,  Purpus  7019  (UC) ;  near  Silver  City,  New  Mexico,  October  8, 
1880,  Greene  (UC) ;  San  Francisco  Mountains,  Arizona,  Leiberg  6840  (US) ;  Bingen,  Klicki- 
tat County,  Washington,  Suksdorf  4602  (DS,  US) ;  Vancouver  Island,  British  Columbia, 
August  16,  1887,  Macoun  (NY,  US);  Clarks  Fork  Valley,  northern  Idaho,  Leiberg  1580 
(Gr,  UC,  NY,  US) ;  Bozeman,  Montana,  Blankinship  304  (hb.  Blankinship) ;  Whiteshore 
Lake,  Saskatchewan,  Macoun  and  Herriot  72832  (NY,  minor  variation  7,  A.  camporum 
Rydberg). 

21c.  Artemisia  campestris  caudata  (Michaux). — Root  biennial,  often  very  large 
when  growing  in  sand-dunes,  but  perhaps  never  perennial;  stem  usually  single  unless 
injured,  erect,  3  to  5  dm.  high,  leafy  at  base  and  up  to  the  inflorescence  or  sparsely  leafy 
above;  leaves  twice  or  thrice  pinnately  divided  into  elongated  diverging  filiform  or  very 
narrowly  linear  divisions  0.5  mm.  or  less  wide,  the  upper  ones  more  simply  cut,  glabrous 
or  sometimes  canescent  when  young  (in  A.forwoodi  Watson,  minor  variation  18) ;  inflores- 
cence a  narrowly  pyramidal  panicle  of  ascending  rather  close  branches,  3  to  10  cm.  broad; 
heads  peduncled,  nodding  or  erect,  narrowly  hemispheric;  involucre  2  to  3  or  rarely  3.5 
mm.  high,  about  as  broad,  glabrous,  yellowish  green;  disk-flowers  5  to  15,  the  corolla 
1.5  to  2.2  mm.  long.  {A.  caudata  Michaux,  Fl.  Bor.  Amer.  2:129  1803.)  Widely, 
distributed  but  most  common  in  the  eastern  and  central  States:  New  Brunswick  and 
Maine  to  Florida,  Texas,  Wyoming,  Washington,  Saskatchewan,  and  Ontario.  (Speci- 
mens seen  from  south  of  Connecticut  and  Illinois  are  without  roots  and  their  identifica- 
tion therefore  not  absolutely  positive.)  Type  locality,  sandy  banks  of  the  Missouri 
River.  Collections:  Pine  Point,  Maine,  Purlin  1097  (N.  E.  Bot.  Club);  Lynn  Beach, 
Massachusetts,  August,  1887,  Summers  (US);  North  Haven,  Connecticut,  Bissell  878 
(Gr);  Hennepin  County,  Minnesota,  August,  1890,  Sandberg  (UC);  Washington  Island, 
Wisconsin,  September  12,  1889,  Shuette  (Gr,  UC) ;  sandy  barrens  near  Oquawka,  Illinois, 
August,  1877,  Patterson  (UC);  sand  dunes  at  Millers,  Indiana,  September  4,  1911, 
Sherff  (US);  Blue  River,  Nebraska,  September,  1888,  Wibbe  (UC);  vicinity  of  Pine 
Grove,  Colorado,  Crandall  2640  (US) ;  Deadwood,  South  Dakota,  Carr  29  (NY,  minor 
variation  IS,  A.  forwoodi  Watson);  Willow  City,  North  Dakota,  September  11,  1899, 
Lunell  (NY,  same  variation);  near  Bingen,  Washington,  August,  1907,  Suksdorf  (NY); 
Brandon,  Manitoba,  Macoun  12247  (NY). 

21d.  Artemisia  campestris  borealis  (Pallas). — Root  perennial;  stems  several, 
crowded  on  a  multicipital  caudex,  1  to  3  dm.  high,  erect  from  a  sometimes  spreading  base; 
densely  leafy  only  below,  sometimes  moderately  leafy  to  midway  of  the  inflorescence; 
leaves  once  or  twice  ternately  divided  into  linear  divisions,  mostly  1  to  2  mm.  wide,  or 


A.    CAMPESTRIS.  123 

with  a  few  extra  lobes  along  the  rachis  and  hence  somewhat  pinnately  divided,  the  upper 
ones  simply  ternate  or  undivided,  glabrous  to  somewhat  silky-villous  and  then  glabrate 
at  least  on  upper  surface;  inflorescence  raceme-like  or  spike-like  to  loosely  paniculate, 
1  to  5  cm.  broad;  lower  heads  peduncled,  the  upper  sessile,  mostly  nodding,  hemispheric; 
involucre  3  to  nearly  4  mm.  high,  3.5  to  4  mm.  broad,  glabrous  or  nearly  so,  yellowish 
green  (or  brownish),  the  bracts  with  brown  medial  line;  disk-flowers  apparently  15  to  30, 
the  corolla  2.2  to  2.6  mm.  long.  {A.  borealis  Pallas,  Reise  3:755,  1776.)  Greenland 
and  Hudson  Bay  to  Vermont,  western  Ontario,  Colorado  (?),  and  Washington,  thence 
probably  far  to  the  north  and  northwest,  since  it  is  reported  from  Kotzebue  Sound 
(Hooker,  Fl.  Bor.  Am.  1:327,  1833)  and  is  not  rare  is  Siberia.  Type  locality,  Siberia. 
Collections:  Grand  Falls,  Newfoundland,  on  ledges  and  talus,  Fernald  and  Wiegand 
6S88  (DS,  Gr,  UC) ;  Gasp^  County,  Quebec,  on  serpentine  detritus,  Collins  and  Fernald 
145  (NY,  UC,  US) ;  Gasp6  County,  Quebec,  on  cliffs,  Collins,  Fernald,  and  Pease  6183 
(UC);  Mount  Mansfield,  Vermont,  Egglesion  2027a  (NY);  Mount  Harvard,  Colorado, 
Clements  31  (NY,  referred  here  because  of  the  glabrous  involucres,  but  doubtless  a  local 
derivative  of  subspecies  spithamaea) ;  near  Banff,  Alberta,  McCalla  2016  (US,  type  of 
A.  maccallae  Rydberg,  minor  variation  22);  White  Horse  Rapids,  Yukon  River,  Macoun 
79015  (NY,  same  variation). 

21e.  Artemisia  campestris  spithamaea  (Pursh). — Root  perennial;  stems  several, 
crowded  on  the  crown,  1  to  4  dm.  high,  erect  or  ascending,  the  base  often  spreading, 
densely  leafy  below,  less  so  up  into  the  inflorescence;  leaves  once  or  twice  ternately  or 
somewhat  pinnately  divided  into  short  linear  or  linear-oblanceolate  divisions,  the  upper 
ones  less  divided  or  entire,  all  densely  silky-pubescent;  inflorescence  spike-hke,  very  dense 
towards  the  summit,  about  0.5  to  1.5  cm.  broad,  or  closely  paniculate  and  up  to  4  cm. 
broad  (form  =  ^.  bourgeauana  Rydberg,  minor  variation  5);  heads  sessile  or  subsessile, 
erect  to  nodding,  hemispheric;  involucre  about  4  mm.  high,  4  to  5  mm.  broad,  densely  vil- 
lous, brownish  except  where  covered  by  the  gray  pubescence;  disk-flowers  15  to  20  or 
more,  the  corollas  about  3  mm.  long.  {A.  spithamaea  Pursh,  Fl.  Am.  Sept.  522,  1814.) 
Greenland  and  the  Arctic  coast  to  Quebec  and  in  the  mountains  to  Colorado  and  northern 
Oregon,  thence  northwest  to  the  Aleutian  Islands  and  Kamchatka.  Type  locality, 
Labrador.  Collections:  Near  Fyllas,  Greenland,  August  2,  1884,  Warming  and  Holm 
(Gr);  Nikok,  western  Greenland,  August  10,  1907,  Hansen  (hb.  Blankinship) ;  island  of 
Omenak,  Greenland,  White  and  Schuchert  163  (US,  intermediate  to  subspecies  borealis, 
some  involucres  glabrous,  some  moderately  pubescent  with  long  loose  hairs) ;  Rama, 
Labrador  coast,  Sornborger  62  (Gr,  US,  intermediate  to  subspecies  borealis);  Okkak, 
Labrador,  Moravian  Fathers  (Gr);  on  serpentine,  Mount  Albert,  Quebec,  Fernald  and 
Collins  268  (NY);  northwestern  Wyoming,  Rose  655  (US);  Cameron  Pass,  Colorado, 
July  31,  1896,  Baker  (NY,  UC);  high  mountains  about  Empire,  Colorado,  Patterson  215 
(Gr,  NY,  UC);  Crestone's,  Sangre  de  Cristo,  Colorado,  September,  1877,  Brandegee 
(UC);  Mount  Henry,  Montana,  Umbach  612  (NY,  US);  gravelly  banks  of  the  Columbia 
River,  Wasco  County,  Oregon,  April  14,  1886,  Suksdorf  (Gr) ;  Biggs,  Oregon,  near  the 
banks  of  the  Columbia  River,  May  31,  1910,  Heller  (NY,  UC,  type  collection  of  A.  ripi- 
cola  Rydberg,  minor  variation  29) ;  summit  of  Olympic  Mountains,  Washington,  August 
28,  1898,  Flett  (US);  Cold  Bay,  Alaska,  Piper  4223  (US,  type  of  A.  manca  Rydberg, 
minor  variation  23);  Petropaulovski,  Kamchatka,  1853-56,  Wright  (Gr,  with  inter- 
mediates to  borealis). 

21/.  Artemisia  campestris  pycnocephala  (Lessing). — Root  perennial;  stems  several 
or  numerous  on  a  stout  woody  caudex,  2  to  6  dm.  high,  erect,  very  leafy  up  to  the  inflor- 
escence; leaves  twice  or  thrice  pinnately  divided  into  linear  or  linear-spatulate  divisions 
0.5  to  1  mm.  wide,  densely  and  permanently  silky-villous;  inflorescence  a  strict  virgate 


124  GENUS   ARTEMISIA. 

panicle,  2  to  10  cm.  broad;  heads  sessile,  erect,  hemispheric;  involucre  3.5  to  4.5  mm.  high, 
3.5  to  4.5  mm.  broad,  densely  villous,  disk-flowers  12  to  25,  the  corolla  2  to  3  mm.  long. 
(Oligosporus  pycnocephalus  Lessing,  Linnaea  6:524,  1831.)  Sandy  beaches  along  the 
Pacific  Ocean  from  Oregon  south  to  Point  Sur,  California.  Type  locality,  California. 
Collections:  Coos  County,  Oregon,  House  4991  (NY);  Samoa,  Humboldt  County,  CaU- 
fornia,  Tracy  3023  (DS,  UC,  US) ;  Bodega  Point,  California,  Eastwood  4801  (SF) ;  West 
Berkeley,  San  Francisco  Bay,  California,  Davy  868  (UC) ;  Point  Sur,  Monterey  County, 
California,  July,  1888,  Brandegee  (UC). 

MINOR  VARIATIONS  AND  SYNONYMS. 

Several  of  the  variations  indicated  below  have  been  assigned  specific  rank  by  other  writers.  This  is  not  sur- 
prising in  view  of  the  striking  superficial  differences  between  some  of  them.  This  unlikeness  is  sometimes  due 
to  varying  amounts  of  pubescence.  Thus,  within  a  single  subspecies  there  may  be  found  some  plants  that  are 
quite  green  and  glabrous  as  well  as  others  that  are  hoary  pubescent.  Again,  the  degree  of  branching  gives  rise 
both  to  spicate  and  loosely  paniculate  inflorescences,  but  with  all  intermediate  stages  represented.  Such  char- 
acters are  so  obviously  ecologic,  as  indicated  especially  by  field  observations,  that  the  resulting  forms  are  not 
given  even  subspecific  rank.  A  large  number  of  varieties  are  recognized  by  European  botanists  (see  especially 
Rouy  in  Rev.  Bot.  Syst.  Geog.  Bot.  1 :295,  1903,  and  Fl.  France  8:293,  1903). 

1.  Artemisia  borealis  Pallas,  Reise  3;  755,  1776.— A.  campeslris  borealis. 

la.  A.  BOREALIS  BEssERi  Torrey  and  Gray,  Fl.  N.  Am.  2:417,  1843.— Based  upon  A.  borealis  purshi 
Besser,  which  see. 

2.  A.  BOREALIS  PUBSHi  Besser,  in  Hooker,  Fl.  Bor.  Am.  1:326,  1833.— Based  upon  A.  spithamaea  Pursh, 
which  see. 

3.  A.  BOREALIS  SPITHAMAEA  Torrey  and  Gray,  1.  c— ^.  campestris  spithamaea. 

4.  A.  BOREALIS  woRMSKiOLDi  Besser,  in  Hooker,  Fl.  Bor.  Am.  1:327,  1833. — The  same  as  A.  campestris 
borealis,  from  the  description.  The  original  specimens  came  from  "Columbia  River  and  Islands,  Northwest 
America"  and  Kotzebue  Sound. 

5.  A.  BOURGEAUANA  Rydberg,  Bull.  Torr.  Club  37:454,  1910.— A  form  of  A.  campestris  spithamaea  charac- 
terized by  a  slightly  taller  habit  and  a  dense,  leafy  panicle.  The  types,  which  came  from  Saskatchewan,  are 
3  to  4  dm.  high  and  therefore  nearly  matched  in  height  by  specimens  from  Cameron  Pass,  Colorado  (July  24, 
1894,  CrandaU,  NY),  which  are  3  dm.  high  but 
with  all  other  features  of  spithamaea.  The 
panicles  in  the  types  are  25  cm.  long  and  3  cm. 
broad.  Although  closely  approached  in  some 
specimens  of  spithamaea,  the  large  size  of  the 
inflorescence  constitutes  the  best  character  of 
the  form. 

6.  A.   CAMPESTRIS    GENUiNA    Herder,   PL         °  " 

Radd.    3:57,    1864. — Probably    the    same    as  Tia.  17.— Inner  bracts  ot  Artemisia  campestria  padfica;  a,  b,  e.hom 

A.  campestris  typica.  specimens  of  genuine  pacifica;  d,  e,  /,  from   specimens 

7.  A.  CAMPORUM  Rydberg,  N.  Am.  Fl.  34:  authentically  determined    as    A.    camporym    Rydberg 
«,-.     .«..%       m,      1                  1  7        1     (•     !•             e  (minor  variation  7).     Collections  represented:  o.Lsioero 

254,  1916.— The  lower  and  less  leafy  form  of  j^gg.  f,  ^acoun  sesu:  c.  Butler  64S:  d.  Clements  1S6: 

A.  campestris  pacifica,  although  authentically  e,  Overholla;  J.    Rydberg  203:    all  in  the  Herbarium  of 

named  specimens  are  often  up  to  7  dm.  high  the  New  York  Botanical  Garden.     All  X  8. 

and  as  leafy  as  in  this.     The  inner  bracts  are 

said  to  be  rounded  as  compared  with  the  acutish  inner  bracts  of  pacifica.  In  order  to  test  the  constancy  of 
this  character,  6  sheets  were  selected  from  the  herbarium  of  the  New  York  Botanical  Garden,  3  of  which  had 
been  determined  for  the  North  American  Flora  as  pacifica,  the  other  3  as  camporum.  Heads  from  these  speci- 
mens were  given  to  the  artist  with  directions  to  draw  to  scale  an  average  inner  bract  from  each,  preserving  the 
original  shape  as  far  as  possible.  The  resulting  drawings  are  shown  in  figure  17,  and  seem  to  indicate  that  the 
shape  of  the  inner  bracts  does  not  here  afford  a  safe  criterion  for  the  separation  of  forms.  The  type  locality 
of  camporum  is  Saskatchewan. 

8.  A.  CANADENSIS  Michaux,  Fl.  Bor.  Am.  2: 128,  1803. — A  variation  of  A.  campestris  borealis.  The  original 
characterization  is  too  brief  to  permit  a  determination  of  the  exact  form.  But  since  the  type  locality  is  Hudson 
Bay,  where  typical  borealis  grows,  there  is  no  reason  to  assume  that  it  is  fundamentally  different  from  that 
subspecies.  In  the  Synoptical  Flora,  Gray  greatly  extended  Michaux's  species  to  include  the  common  small- 
headed  form  of  the  western  United  States  now  referred  to  subspecies  pacifica  and  separated  this  from  his  A. 
borealis  Pallas,  chiefly  on  the  numerous  heads  in  a  compound,  oblong  or  pyramidal,  virgate  panicle.  But  Gray 
himself  admitted  that  the  panicle  was  reduced  in  northern  forms.  It  proves  impossible  to  use  the  form  of 
the  inflorescence  to  distinguish  varieties  in  this  region.    The  original  figure  of  Pallas  (Reise,  3:129,  1776) 


A.    CAMPESTRIS.  125 

shows  spicate  clusters  on  the  same  plant  with  a  paniculate  one.  A  plant  from  the  Gasp6  Peninsula  (Fernald 
and  Collins  754)  possesses  one  paniculate  and  two  spicate  stems,  and  Fernald  states  that  the  inflorescence 
varies  with  the  situation.  In  moist  protected  soils  the  plants  are  larger  and  the  clusters  paniculate,  while  in 
drier  or  more  exposed  places  they  are  reduced,  and  the  inflorescence  becomes  spicate.  In  recent  floras  canaden- 
sis is  characterized  with  green  involucres  and  borealis  with  brown,  but  these  colors  are  not  sharply  defined  in 
the  plants  themselves. 

9.  A.  CAUDATA  Michaux,  Fl.  Bor.  Am.  2:129,  1803. — A.  campestris  caudata. 

10.  A.  CAUDATA  CALVENS  Lunell,  Am.  Midi.  Nat.  2:188,  1912. — From  the  description  this  appears  to  be  the 
form  of  A.  campestris  caudata  in  which  the  herbage  is  thickly  tomentulose  when  young.  Type  locality,  in 
gravel  at  Willow  City,  Bottineau  County,  North  Dakota. 

11.  A.  COMMUTATA  DOUGLASIANA  Besser,  Bull.  Soc.  Nat.  Mosc.  8:70,  1835.— Referred  in  N.  Am.  Fl.  to  A. 
camporum  Rydberg,  here  considered  a  minor  form  of  A.  campestris  pacifica.    Type  locality,  Saskatchewan. 

12.  A.  COMMUTATA  HOOKERIANA  Besser,  1.  c.  70,  1835. — Same  as  A.  desertorum  hookeriana,  which  see. 

13.  A.  COMMUTATA  RiCHARDSONiANA  Besser,  1.  c.  74,  1835. — Based  on  A.  desertorum  richardsoniana,  which  see. 

14.  A.  DESERTORUM  DOUGLASIANA  Bcsser,  in  Hooker,  Fl.  Bor.  Am.  1:325,  1833. — Referred  in  N.  Am.  Fl.  to 
A.  camporum  Rydberg,  which  is  here  considered  as  a  minor  form  of  A.  campestris  pacifica.  Type  locality 
not  stated. 

15.  A.  DESERTORUM  HOOKERIANA  Bcsscr,  1.  c,  325,  1833. — Apparently  includes  two  or  more  of  the  subspecies 
of  A.  campestris.     Distribution  originally  given  as  throughout  Canada  and  to  the  Arctic  Circle. 

16.  A.  DESERTORUM  RicH.*.RDSONiANA  Besser,  1.  c,  325,  1833. — Referred  in  N.  Am.  Fl.  to  A.  maccallae, 
which  is  here  considered  as  a  minor  form  of  A.  campestris  borealis,  but  since  it  was  first  described  as  having  ashy- 
sericeous  involucres  it  is  more  likely  the  subspecies  spithamaea.  Original  distribution  given  as  throughout 
Canada  and  thence  to  the  Arctic  Circle. 

17.  A.  DESERTORUM  scouLERiANA  Bcsscr,  1.  c,  325,  1833. — One  of  the  subspecies  of  A.  campestris,  probably 
pacifica.    Type  locality.  Fort  Vancouver  and  Straits  of  de  Fuca. 

18.  A.  FORWOODi  Watson,  Proc.  Am.  Acad.  25: 133,  1890. — A.  campestris  caudata,  but  a  form  with  the  leaves 
mostly  canescent  with  a  short  villous  pubescence.  Type  locality.  Black  Hills  of  South  Dakota.  This  is  chiefly 
a  western  variation,  but  ranges  east  at  least  to  Point  Edward  on  Lake  Huron  {Macoun  26S4S),  while  typical 
caudata  occurs  as  far  west  as  Wyoming  (according  to  Rydberg,  N.  Am.  Fl.). 

19.  A.  FORWOODI  var.  calvens  Lunell,  Am.  Midi.  Nat.  5:68,  1917. — A.  campestris  caudata.  (See  note  under 
A.  caudata  calvens.) 

20.  A.  groenlandica  Wormskiold,  Fl.  Dan.  27 :  10, 1818.-^4.  campestris  spithamaea.  Type  locality,  Green- 
land. 

21.  A.  LEWisi  Torrey  and  Gray,  Fl.  N.  Am.  2:417, 1843  (excluding  synonymy). — A.  campestris  caudata,  but 
a  form  with  heads  in  a  large,  open  panicle.    Type  locality,  Missouri. 

22.  A.  maccallae  Rydberg,  N.  Am.  Fl.  34:254,  1916. — A.  campestris  borealis.  Separated  because  of  the 
short  outer  bracts,  these  about  one-half  as  long  as  the  inner.  The  rather  numerous  heads  are  soon  ascending  or 
erect.    Type  locality,  gravelly  slopes  of  Tunnel  Mountain,  vicinity  of  Banff,  Alberta. 

23.  A.  manca  Rydberg,  N.  Am.  Fl.  34:256,  1916. — A.  campestris  spithamaea.  This  is  a  dwarf,  compact 
form  of  the  far  north,  differing  only  in  the  lower  stature  (5  to  7  cm.)  and  short  leaves  (1  to  2  cm.).  Type  local- 
ity, Cold  Bay,  Alaska. 

24.  A.  PACHTSTACHTA  De  CandoUe,  Prodr.  6:114,  1837. — A.  campestris  pycnocephala.  Erroneously  referred 
by  De  Candolle  to  the  section  Abrotanum,  although  also  properly  placed,  but  with  erroneous  distribution,  in 
the  section  Dracunculus  under  the  name  A.  pycnocephala. 

25.  A.  PACIFICA  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:401,  1841.— A.  campestris  pacifica. 

26.  A.  peucedanifolia  Jussieu;  Besser,  Bull.  Nat.  Soc.  Mosc.  8:91,  1835. — A.  campestris  borealis. 

27.  A.  pycnocephala  De  Candolle,  Prodr.  6:99,  1837. — A.  campestris  pycnocephala. 

28.  A.  PYCNOSTACHYA  Nuttall,  Trans.  Am.  Phil.  Soc.  11,-7:401,  1841.— A.  campestris  pycnocephala.  Obvi- 
ously an  error  in  name. 

29.  A.  RiPicoLA  Rydberg,  N.  Am.  Fl.  34:256,  1916.— A.  campestris  spithamaea.  In  the  North  American 
Flora  this  is  separated  from  spithamaea  in  the  key  by  the  narrowly  linear  instead  of  linear-oblanceolate  segments 
of  the  basal  leaves,  but  these  are  slightly  oblanceolate  as  stated  in  the  description.  Furthermore,  specimens  of 
the  type  collection  from  Biggs,  Oregon,  are  almost  exactly  matched  by  others  from  the  high  mountains  of  Colo- 
rado (for  example,  Cameron  Pass,  July  31,  1896,  Baker,  and  Eagle  Mountain,  August  12,  1913,  Allen).  It  thus 
seems  that  neither  constant  morphologic  characters  nor  geographic  distribution  gives  support  to  this  form. 

30.  A.  SCOULERIANA  Rydberg,  Bull.  Torr.  Club  33: 157,  1906.— Based  upon  A.  desertorum  scouleriana  Besser, 
which  see. 

31.  A.  SPITHAMAEA  Pursh,  Fl.  Am.  Sept.  522,  1814.— A.  campestris  spithamaea. 

32.  A.  VARIABILIS  AMERICANA  Besser,  Bull.  Soc.  Nat.  Mosc.  8:24,  1835.— A.  campestris  caudata  but  a  form 
with  large  panicles. 

33.  OuGosPORUs  PTCNOCEPHALUs  Lessing,  Linnaea  6:524,  1831. — A.  campestris  pycnocephalus. 


126  GENUS   ARTEMISIA. 

RELATIONSHIPS. 

The  species  of  Artemisia  most  closely  connected  phylogenetically  with  A.  campestris 
are  natives  of  Asia  or  possibly  of  Europe.  Of  these,  A.  commutata  Besser  is  so  close  that 
it  should  be  merged  into  it,  as  has  been  already  done  by  some.  As  a  subspecies,  or  series 
of  subspecies,  for  it  passes  into  numerous  forms  similar  to  those  occurring  in  America, 
commutata  stands  between  typica  and  the  other  perennials  described  above.  Its  distribu- 
tion from  the  Caucasus  to  Baikal  and  Davuria,  in  Siberia,  together  with  its  trait  of 
breaking  up  into  forms  similar  in  character  to  ours,  suggests  that  it  may  represent  the 
ancestral  strain  which,  crossing  the  Bering  Straits,  has  given  rise  to  at  least  some  of  the 
American  subspecies.  A  coordination  between  the  Siberian  and  American  forms  is 
impossible  at  the  present  time  from  a  lack  of  field  knowledge.  Another  Siberian  species 
of  close  relationship  is  A.  desertorum  Sprengel,  to  which  several  of  the  American  forms 
were  once  assigned  by  Besser.  This  has  all  of  the  essential  characters  of  campestris,  but 
is  perhaps  to  be  retained  because  of  its  much  wider  leaf-segments.  The  only  American 
Artemisia  closely  allied  to  campestris  is  A.  dracunculus,  and  even  here  the  separation 
probably  took  place  in  the  Old  World.  There  is  no  constant  floral  difference  between  the 
two,  but  the  much  more  pronounced  segmentation  of  the  leaves  and  the  tendency  to 
produce  most  of  these  in  a  basal  rosette  give  to  campestris  a  very  different  aspect. 

In  taking  up  the  segregates  of  this  cosmopolitan  species  it  is  first  noted  that  the  typical 
form  is  common  on  the  plains  of  Europe  and  western  Asia.  In  America  it  is  known 
from  only  a  few  isolated  stations  along  the  Atlantic  seaboard,  where  it  is  probably 
adventive  from  Europe.  It  is  a  tall,  perennial  herb  with  numerous  stems  from  the  base, 
very  narrow  leaf-segments,  and  small,  ovoid  heads  in  an  open,  loosely  branched  inflores- 
cence. On  the  plains  and  in  the  lower  mountains  of  the  western  States  grows  a  subspe- 
cies so  similar  that  it  is  easily  mistaken  for  typica.  This  is  pacifica  (often  erroneously 
referred  to  canadensis).  In  this  the  heads  are  usually  broader  at  the  same  stage  of 
development,  but  they  sometimes  so  closely  match  the  heads  of  the  Old  World  type  that 
the  two  can  not  be  distinguished  by  this  feature  alone.  The  pubescence  in  pacifica  is 
more  dense  and  persistent  than  the  general  run  of  typica,  but  some  mature  specimens  of 
the  latter  are  densely  sericeous  (Lower  Austria,  November  3,  1898,  Klebs).  A.  commu- 
tata, which  is  not  specifically  separable  from  campestris,  is  said  by  Ledebour  (Fl.  Rossica 
2:567,  1845)  to  vary  from  apparently  glabrous  to  villous-sericeous.  The  most  nearly 
constant  character  of  subspecies  pacifica  is  its  compact  inflorescence,  the  branches  of 
which  are  strict  and  ascending,  not  outwardly  curved  as  in  the  other.  Since  even  this 
distinction  requires  a  series  of  specimens  for  its  practical  use,  and  since  the  other  char- 
acters are  shown  to  be  of  but  little  moment,  it  now  seems  impossible  to  retain  pacifica  in 
more  than  subspecific  rank. 

The  Old  World  type  of  campestris  is  more  closely  approached  in  size  and  shape  of  head 
and  in  the  inflorescence  by  subspecies  caudata,  of  the  eastern  and  central  States,  but  this 
is  unique  in  the  genus  in  having  a  biennial  taproot  and  usually  but  a  single  stem,  the 
latter  character  perhaps  a  result  of  the  biennial  habit.  These  traits  are  so  strikingly 
constant  that  the  subspecies  seems  possibly  not  to  have  arisen  from  any  of  the  others  here 
described,  but  from  some  Old  World  form  with  which  we  are  not  familiar.  Taxonomi- 
cally  it  is  the  most  distinct  of  all  of  the  subspecies  except  pycnocephala. 

The  next  two  subspecies,  that  is,  borealis  and  spithamaea,  are  both  of  northerly  dis- 
tribution, scarcely  reaching  the  United  States  except  in  the  higher  mountains.  They 
extend  from  Greenland  to  the  Aleutian  Islands,  and  borealis  has  its  type  locality  in  Siberia. 
The  influence  of  the  boreal  habitat  is  seen  in  the  large  size  of  the  heads,  in  the  reduced 
inflorescence,  and  in  the  strictly  perennial  root.  This  stout  root  supports  at  the  surface 
a  branching  caudex  from  which  arise  several  or  numerous  annual  stems.  Fundamentally 
this  is  not  different  from  the  habit  of  typica  and  pacifica,  but  the  caudex  is  more  branched, 


A.    CAMPESTRIS. 


127 


sometimes  cespitose,  and  the  flowering  stems  are  usually  shorter.  It  may  appear  desir- 
able to  some  to  set  these  forms  off  as  a  species  distinct  from  campestris  and  pacifica  on 
the  basis  of  the  larger  heads,  but  a  glance  at  table  1 1  will  show  the  impossibility  of  this 
course.  In  fact,  the  overlapping  is  much  greater  than  indicated  by  the  few  specimens 
there  reported  upon.  Neither  Besser  nor  Gray  was  able  to  find  specific  distinctions 
between  canadensis  (here  included  with  subspecies  borealis)  and  pacifica.     Moreover, 


Fio.  18. —  Phylogenetic  chart  of  the  subspecies  of  Artemisia  campeslria. 

this  last-named  subspecies  exhibits  forms  intergrading  with  spithamaea.  For  example, 
3  sheets  at  the  National  Herbarium  from  Glacier  National  Park  (Standley  17307,  17331, 
17716)  represent  plants  3  to  5  dm.  high  and  with  the  usual  broad  panicle,  while  another 
(Standley  16688)  from  the  same  park  is  a  dwarf  only  1.5  dm.  high,  the  inflorescence  less 
than  1  cm.  broad  and  yet  with  heads  much  too  small  for  subspecies  spithamaea.  The 
northern  subspecies  borealis  and  spithamaea  differ  between  themselves  only  in  very  minor 
characters  and  in  pubescence.  It  would  be  entirely  logical  to  unite  them,  and  recognize 
several  ecologic  forms,  but  the  marked  difference  in  the  appearance  of  the  extremes  and 
the  absence  of  intergrades  over  certain  large  areas  render  the  subspecific  rank  of  some 
use.  Still  further  segregations  have  been  made,  but  these  are  based  upon  habital  and 
other  characters  now  known  to  be  of  little  taxonomic  value.  They  are  here  indicated 
under  minor  variations. 

The  most  remarkable  deviation  within  the  species  is  represented  by  subspecies  pycno- 
cephala,  a  form  restricted  to  the  coastal  sands  of  northern  California  and  southern  Oregon 
and  at  least  1,000  km.  removed  from  any  of  the  others.  Its  robust  habit  and  coarse 
pubescence  give  to  it  an  aspect  so  unique  that  it  seems  scarcely  to  belong  to  the  present 


128 


GENUS   ABTEMISIA. 
Table  11. — Variation  in  the  subspecies  of  Artemisia  campestris. 


No.  of 
disk- 
flowers. 


Total 
no.  of 
flowers. 


Length  of 
disk- 
corolla. 


Subspecies  typica: 

Berlin  Botanical  Garden 

Stendel,  Germany 

Kolpenick,  Germany 

Carlsruhe,  Germany.  . . , 

Tirol,  Austria 

Upsala,  Sweden 

Finland 

Do 

Le  Mans,  France 

Suffolk,  England 

Europe 

Waterbury,  Conn 


617460  US 

NY 

6560  Baker 

545707  US 

343717  US 

US 

UC 

uc 

6492  Baker 

812960  US 

29728  UC 

Or. 


Average 

Subspecies  pacifica: 

Inyan  Kara  Divide,  Wyo. 

Laramie,  Wyo 

New  Windsor,  Colo 

Tolland,  Colo 

Austin  Bluffs,  Colo 

Manitou,  Colo 

Cafion   City,   Colo 

Turquoise  Lake,  Colo.. . . 

West-central  Colo 

Silver  City,  N.  Mex 

San  Francisco  Mt9.,Ariz. 
La  Sal  Mountains, Utah. 
Clarks  Fork  Valley,  Ida. 


Average 

Subspecies  caudala: 

Frenchville,  Me 

Marthas  Vineyard, Mass. 
Washington  Island,  Wis. 

Oquawka,  111 

Peoria,  111 

Evanston,  111 

Blue  River,  Nebr 


29730  UC 

146507  UC 

34331  UC 

10491  CI 
CI 
CI 

172665  UC 

11061  CI 

34514  UC 

29732  UC 

193457  UC 

135383  UC 

154393  UC 


(Femald)  Gr 
29735  UC 
181940  UC 
172666  UC 
91216  UC 
193517  UC 
193608  UC 


Average 

Subspecies  borealia: 

Table  Mountain,  Nfd... 

Exploits  River,  Nfd 

Mount  Albert,  Quebec. 

Do 

Do 

Gaspg  County,  Quebec. 

Do 


Gr 

201606  UC 
Gr 
Gr 
Gr 

147968  UC 
69740  UC 


Average 

Subspecies  apithamaea: 
Clear  Creek,  Colo.. 
Saguache,  Colo. .  .  . 
Biggs,  Oreg 


29726  UC 
91237  UC 
196037  UC 


Average 

Subspecies  pycnocephala: 

Lake  Earl,  Calif 

Opposite  Eureka.Calif. 
West  Berkeley,  Calif. . 

Del  Monte,  Calif 

Point  Sur,  Calif 


128619  UC 
164826  UC 

71897  UC 
184483  UC 

91213  UC 


Average. 


3.0 
2.5 
2.0 
2.5 
2.0 
2.0 
2.8 
3.0 
2.6 
2.8 


4.2 
4.0 
4.0 


2.0 
1.8 
2.6 
2.6 
2.4 
2.6 
2.4 
2.8 
2.6 
2.5 
2.9 
2.0 


11  11 
9  9 
9  10 

12  13 
9  10 

10  10 

10 

10  9 


12  14 
11  10 

14  16 

15  15 
10  10 
14  16 

17  14 
28  28 

18  15 


2.4 
1.8 
2.4 
2.4 
2.1 
2.4 


2.6 
2.3 
2.5 
2.5 
2.5 
2.5 
2.2 
3.0 


10  11 
10  9 

12  10 
15  10 

13  12 
10  10 
12  13 

14  11 
12  12 

9  11 
12  8 

10  12 

11  12 


15  17 
12  15 
12  10 

16  13 
12  17 
15  17 
15  14 
15  11 

11  13 

12  10 
9  11 

13  12 
9  10 


15  16 
17  19 

13  10 

22  18 
12  14 

14  10 

11  13 

23  13 
22  18 
19  14 

8  8 
10  16 

12  13 


24  31 
29  27 
26  27 
38  24 
33  31 
31  24 
17  19 
23  28 
21  23 


2.0 
1.8 
2.0 
young 
Do. 
Do. 
2.1 
2.1 
2.0 
2.0 


11 


12 


14 


27 


22  20 

14  13 
8  7 

13  16 
11  14 
13  15 

15  14 


11  9 
8  6 

11  9 
13  13 
20  13 

12  11 


13  13 
6  8 
9  10 


21  22 
17  17 

17  15 

18  14 
24  25 
24  31 
23  22 


13 


10 


10 


20 


3.4 
3.6 
3.7 


15  17 
15  18 
17  15 

14  16 

15  14 
17  13 
12  13 


13  13 
21  19 

17  16 

13  15 

14  14 

15  13 

18  14 


12  15 

20  25 
27  28 
25  30 
17  17 

21  20 
17  22 


25  28 
41  44 
44  44 
38  45 
31  31 
36  33 
35  36 


15 


15 


21 


15  11 

11  12 

15 


3.0 
2.8 
3.0 


A.    CAMPESTEIS.  129 

assemblage,  but  in  all  essentials  it  is  so  close  to  some  of  the  other  subspecies,  especially 
the  tall  (bourgeauana)  forms  of  spithamaea  that  a  workable  key  can  not  be  constructed 
that  will  satisfactorily  separate  it.  It  is  undoubtedly  a  derivative  of  some  boreal  form 
which  has  become  isolated  and  has  responded  to  protection  and  the  more  genial  climate 
through  the  development  of  an  exceptionally  robust  habit  and  other  characters  espe- 
cially suited  to  its  southerly  maritime  habitat.  This  view  finds  some  substantiation  in 
the  fact  that  while  the  plants  of  the  middle  California  coast  represent  the  extreme  type 
as  to  robustness,  enlarged  inflorescence,  and  spreading  pubescence,  those  from  farther 
north  have  these  characters  much  less  developed.  Thus,  a  collection  from  Lake  Earle, 
Del  Norte  County,  California  (Univ.  Calif.  128619),  has  sparsely  leafy  stems  only  2  dm. 
high  and  leaves  small  in  proportion,  while  the  inflorescence  is  spike-like  and  only  1.2  cm. 
broad  at  the  broadest  place.  These  plants  have  the  whole  aspect,  although  not  quite 
the  pubescence,  of  some  forms  of  spithamaea. 

Another  collection  {Tracy  3023)  from  the  next  county  south  of  Del  Norte  is  interme- 
diate in  these  characters  between  the  Lake  Earle  collection  and  the  common  form  of 
middle  California.  The  northern  ancestor  of  this  subspecies  is  perhaps  to  be  found 
in  spithamaea,  of  which  some  forms  are  2  to  3  dm.  high  and  with  an  inflorescence  1  to  4 
cm.  broad,  thus  completely  overlapping  the  dimensions  of  pycnocephala.  In  pubescence, 
also,  they  are  scarcely  distinct  from  this  coastal  plant,  so  that  if  it  were  not  for  the 
habitat  they  would  quite  certainly  be  called  the  same.  Such  plants  come  from  sandy 
river  banks  at  Bingen,  Klickitat  County,  Washington  {Suksdorf  2685  and  2686,  both 
at  the  National  Herbarium,  where  determined  as  A.  ripicola  Rydberg).  It  is  also  of 
interest  to  find  that  a  variety  with  some  of  these  characteristics  has  been  recognized 
in  plants  growing  on  sandy  shores  in  France.  This  is  described  as  a  stout  plant  with 
short  and  broad  leaf-segments  and  comparatively  large  heads.  To  it  has  been  given 
the  name,  A.  campestris  var.  maritima  Lloyd  (see  Coste,  Fl.  France  2:333,  1903). 

The  relationships  of  the  subspecies  of  A.  campestris  are  graphically  represented  in  the 
accompanying  diagram  (p.  127). 


Artemisia  campestris  is  tjTDically  a  rosette-former,  though  this  habit  is  more  marked 
in  the  biennial  than  the  perennial  forms.  For  the  most  part  the  subspecies  are  serai 
dominants,  but  pacifica  in  particular  is  an  important  society  of  the  mixed-prairie  climax. 
Typica,  caudata,  and  pycnocephala  regularly  form  consocies  or  socies  on  sandy  shores 
and  dunes,  from  which  they  sometimes  find  their  way  into  waste  places.  Pacifica  is 
one  of  the  most  unpalatable  of  Artemisias  to  stock  and  hence  is  excelled  only  by  A. 
frigida  as  an  indicator  of  overgrazing.  The  pioneering  quality  of  the  species  is  also  shown 
in  the  frequent  occurrence  of  pacifica  in  disturbed  soils,  especially  sands  and  gravels. 


The  field  sagewort  is  a  common  weed  on  many  of  the  stock  ranges  of  the  West,  espe- 
cially in  the  northern  Rocky  Mountain  States,  but  it  is  so  unpalatable  that  it  is  grazed 
only  when  all  other  sources  fail.  It  occasionally  tides  animals,  especially  sheep,  over 
exceptionally  hard  seasons,  but  its  value  for  this  purpose  is  slight.  In  these  same  regions 
the  herbage  is  gathered,  dried,  and  placed  upon  the  market  as  a  substitute  for  imported 
sage,  used  in  cookery  and  somewhat  in  medicine,  and  the  name  of  "wild  hair  tonic" 
sometimes  applied  to  it  indicates  that  perhaps  it  is  employed  to  stimulate  the  growth  of 
the  hair.  The  properties  of  the  essential  oil  present  in  the  herbage  of  subspecies  caudata 
have  been  studied  by  Rabek  (Pharm.  Rev.  24:324,  1906).  It  is  one  of  the  causes  of 
hay-fever,  as  shown  by  tests  made  in  the  Rocky  Mountain  region. 


130  GENUS   AKTEMISIA. 

22.  ARTEMISIA  FILIFOLIA  Torrey,  Ann.  Lye.  N.  Y.  2:211,  1828.    Plate  16. 
Sand  Sagebrush. 

A  rounded  shrub,  5  to  12  dm.  high,  mildly  and  pleasantly  scented ;  stems  freely  branched 
throughout,  the  older  parts  with  a  close  and  smooth  dark-gray  or  blackish  bark,  the 
numerous  slender  twigs  striate  beneath  a  canescent  pubescence;  principal  leaves  sessile, 
often  with  fascicled  ones  in  their  axils,  filiform,  3  to  8  cm.  long,  less  than  0.5  mm.  wide 
at  base,  ternately  divided  into  long  filiform  divisions  or  some  of  them  entire,  canescent ; 
upper  leaves  but  little  reduced,  more  often  entire,  ascending  or  incurved,  canescent; 
inflorescence  a  narrow,  dense,  leafy  panicle,  10  to  30  cm.  long  by  1  to  5  cm.  broad; 
heads  heterogamous,  crowded,  nodding  on  recurved  peduncles;  involucre  subglobose, 
1.5  to  2  mm.  high  and  nearly  as  broad;  bracts  5  to  9,  the  outer  ones  short  and  thick,  the 
inner  ones  thinner,  broadly  elliptic,  obtuse,  all  densely  canescent  on  exposed  parts,  none 
scarious;  receptacle  smooth  and  naked;  raj^-flowers  2  or  3,  fertile,  corolla  tubular,  about 
1  mm.  long;  disk-flowers  1  to  6,  sterile,  corolla  broadly  funnelform,  5-toothed,  1.5  to  2 
mm.  long,  resinous-glandular;  style  of  disk-flowers  1  to  1.5  mm.  long,  either  cup-shaped 
at  the  erose  summit,  the  branches  being  entirely  fused,  or  shortly  bifid  and  the  lobes 
with  erose  margins ;  achenes  ellipsoid,  narrowed  to  the  corolla,  either  smooth  or  with  4  or  5 
raised  ribs,  glabrous,  those  of  the  disk-flowers  abortive. 

Wyoming  and  western  Nebraska  to  Texas,  Chihuahua,  Arizona,  Nevada,  and  Utah. 
Type  locality  not  given.  Collections:  Uva,  Laramie  County,  Wyoming,  Nelson  8636 
(Gr,  NY,  UC);  North  Denver,  Colorado,  Eastwood  32  (Gr,  UC,  many  of  the  heads 
transformed  into  galls) ;  Deuel  County,  western  Nebraska,  Rydberg  206  (NY) ;  Tribune, 
Greeley  County,  Kansas,  September  18,  1893,  Reed  (UC);  near  Alva,  Oklahoma 
(common)  Stevens  2811  (Gr);  Box  Springs,  Texas,  Tracy  8155  (NY);  near  Del  Norte, 
Chihuahua,  Pringle  770  (Gr,  NY,  UC,  US) ;  Mesilla  Valley,  Dona  Ana  County,  New 
Mexico,  October  2,  1889,  Wooton  (UC,  many  of  the  heads  transformed  into  galls); 
Willcox  Flat,  southeastern  Arizona,  Shreve  J^257  (SF,  UC) ;  above  Rioville,  southeastern 
Nevada,  Jones  5036  (UC);  between  Kanab  and  Carmel,  Utah,  Jones  60Jt7  (NY,  UC). 

MINOR  VARIATION. 

1.  Artemisia  plattensis  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:397,  \?A\.—A.  Jilijolia.  Separated  from  A. 
filifolia  only  on  its  inflorescence,  which  is  described  as  a  loose  and  regularly  simple-branched  panicle.  All 
degrees  of  density  of  inflorescence  may  be  observed  in  a  field  of  these  plants.  Type  locality,  upper  plains  of 
the  Platte  River. 

RELATIONSHIPS. 

The  only  American  Artemisia  which  can  claim  close  relationship  is  A.  pedatifida, 
as  will  be  pointed  out  under  that  species.  In  the  opinion  of  Rydberg,  these  two  are 
suflBciently  well  set-off  from  the  other  species  of  his  subgenus  Dracunculus  to  form  a 
separate  section.  This  he  distinguishes  by  the  shrubby  or  subshrubby  habit  and  the 
"usually  more  or  less  2-cleft"  style  of  the  disk-flowers  (N.  Am.  Fl.  34:245,  1916). 
This  cleavage  of  the  style  is  fairly  well  marked  in  the  specimens  examined  of  pedatifida, 
although  even  in  this  species  there  is  a  partial  fusion  in  some  cases,  but  in  filifolia  it  is 
often  obscure  and  sometimes  it  fails  entirely.  Since  species  of  Rydberg's  section  with 
entire  styles,  particularly  campestris,  also  have  evident  branches  in  somewhat  over  30 
per  cent  of  the  flowers  examined,  this  feature  is  seen  to  be  too  variable  to  be  of  much 
real  value  as  a  specific  or  sectional  criterion.  It  is,  however,  of  great  assistance  in 
working  out  the  phylogeny  of  the  species  of  this  group.  For  example,  since  the  original 
condition  undoubtedly  was  one  in  which  the  branches  were  distinct  for  some  distance, 
entire  styles  are  to  be  looked  upon  as  the  result  of  fusion  of  these  branches  and  therefore 
as  representing  a  more  advanced  type  of  plant.  According  to  this  view,  A.  filifolia 
is  intermediate  in  its  development,  for,  while  its  style  is  usually  branched,  in  some  cases 
the  parts  are  completely  fused  and  terminated  by  an  unbroken  cup-like  border  (e.  g., 


A.    FILIFOLIA — A.  PEDATIFIDA.  131 

plants  from  Canon  City,  Colorado,  August  30,  1919,  Hall).  This  allies  it  with  A. 
campestris  and  A.  pedatijida,  which  are  also  in  a  transitory  stage  as  regards  this  character, 
and  places  it  below  A.  dracunculus,  in  which  the  branches  are  usually  completely  fused. 
This  last  species,  however,  is  less  highly  developed  in  certain  other  particulars,  such  as 
the  herbaceous  habit,  and  is  therefore  provisionally  retained  first  in  the  sequence  of 
species.  The  results  of  a  detailed  examination  of  style-branches  are  given  in  the  intro- 
ductory remarks  on  criteria  (p.  38). 

In  comparing  A.  filifolia  with  species  outside  its  own  section,  one  is  impressed  with 
the  remarkable  similarity  to  A.  calif omica.  This  extends  to  the  habit,  foliage,  inflores- 
cence, and  ecologic  behavior.  If  such  a  relationship  exists,  calif  omica  is  obviously  the 
more  primitive,  chiefly  because  of  its  fertile  disk-achenes,  larger  number  of  flowers  in 
the  head,  and  evidently  closer  connection  with  the  genus  Crossostephium.  The  deriva- 
tion of  filifolia  would  involve  a  considerable  reduction  in  the  number  of  flowers,  an 
abortion  of  the  central  achenes,  and  the  rounding  of  the  summit  of  the  ray-achenes, 
as  well  as  the  smoothing  out  of  the  angles  of  these  latter.  It  is  also  to  be  noted  that  in 
A.  calif  arnica  there  is  no  tendency  toward  a  fusion  of  the  style  branches.  Therefore, 
while  this  connection  is  considered  as  possible,  it  is  not  demonstrable  with  the  evidence 
now  at  hand. 

ECOLOGY. 

Artemisia  filifolia  resembles  both  A.  iridentata  and  calif  arnica  in  life-form,  but  is  more 
like  the  latter  in  its  rounded  bushy  habit.  It  is  typically  a  subclimax  dominant  of  sandy 
soils,  and  perhaps  the  most  widespread  shrub  on  inland  dunes  and  sandhills  from 
Nebraska  to  Arizona.  In  the  north  especially  it  often  forms  pure  consocies,  but  south- 
ward it  is  usually  associated  with  Yticca,  Chrysothamnus,  Dalea  scoparia,  PoUomintha 
incana,  or  Atriplex  canescens.  Toward  the  close  of  the  succession,  the  sand  sagebrush 
persists  for  a  long  time  in  the  mixed  prairie  cover,  producing  the  appearance  of  a  savan- 
nah. It  is  one  of  the  most  characteristic  indicators  of  sand,  and  changes  in  abundance 
serve  to  denote  the  amount  of  sand  in  the  soil.  The  heads  are  often  enlarged  and  trans- 
formed into  galls  by  species  of  Rhopalomya. 

USES. 
The  value  of  the  sand  sagebrush  as  a  browse  shrub  depends  upon  the  region  where  it 
grows.  In  the  grassland  districts  it  is  seldom  much  eaten,  because  of  the  abundance  of 
other  food.  Thus  it  is  reported  from  Texas  and  the  Rocky  Mountain  States  north  to  the 
Dakotas  as  of  little  value,  and  the  normal  development  of  the  plants  verifies  this  state- 
ment. But  in  the  more  arid  southwest,  particularly  New  Mexico  and  Arizona,  the  plant 
is  reported  to  be  of  considerable  value,  and  the  closely  cropped,  irregular  shrubs  give 
evidence  of  close  browsing.  In  the  last-named  State  it  is  of  importance  only  in  the 
eastern  part,  since  it  becomes  sparse  toward  the  west  and  is  entirely  wanting  as  the 
California  line  is  approached.  Attention  should  be  given  to  this  species  as  a  cause  of 
hay-fever,  since  it  possesses  all  of  the  necessary  characteristics  and  is  fairly  common  near 
settled  districts,  especially  in  eastern  Colorado. 

23.  ARTEMISIA  PEDATIFIDA  Nuttall,  Trans.  Am.  Phil.  See.  II,  7:399,  1841.    Plate  16. 
BiRDFOOT  Sagebrush. 

A  low  perennial  subshrub  with  a  tough  woody  root,  0.5  to  1.5  dm.  high,  the  odor 
unknown;  stems  numerous,  erect  from  the  short  woody  base  (this  with  fibrous  exfoliating 
bark),  obscurely  striate,  cinereous-pubescent;  basal  leaves  tufted,  petioled,  1  to  2  cm. 
long  including  the  petiole  and  nearly  as  wide  across  the  lobes,  once  or  twice  ternately 
divided  into  narrowly  spatulate  or  nearly  linear  short  divisions,  gray  with  a  fine  dense 
pubescence;  upper  leaves  smaller,  with  few  divisions  or  entire,  permanently  cinereous 


132  GENUS   ARTEMISIA. 

like  the  lower;  inflorescence  raceme-like  or  spike-like,  sparsely  leafy,  1  to  7  cm.  long  by 
about  0.5  cm.  broad;  heads  heterogamous,  short-peduncled  or  subsessile,  erect;  involucre 
hemispheric,  about  3.5  mm.  high,  3  to  4  mm.  broad;  bracts  6  to  10,  round-oval,  obtuse 
or  slightly  acute,  moderately  unequal,  scarious-margined,  the  outer  ones  densely  tomentu- 
lose;  receptacle  naked;  ray-flowers  4  to  7,  fertile,  corolla  1.5  to  2  mm.  long,  very  slender, 
constricted  at  the  few-toothed  summit;  disk-flowers  5  to  10,  sterile,  corolla  tubular- 
funnelform,  3  to  3.5  mm.  long,  5-toothed,  rose-colored  toward  the  summit,  glabrous; 
style  of  disk-flowers  2.5  to  nearly  3  mm.  long,  2-cleft  at  summit,  the  branches 
penicillate  at  apex  or  the  branches  sometimes  fused  along  one  sinus,  the  other  remaining 
open,  probably  completely  fused  in  some  cases;  ach^nes  ellipsoid,  faintly  ribbed,  glabrous, 
those  of  the  disk-flowers  wanting. 

Northern  Rocky  Mountains  on  dry  plateaus  and  ridges.  Wyoming,  Idaho,  and 
probably  Montana.  Type  locality,  arid  plains  of  Lewis  (Snake)  River.  Collections: 
Steamboat  Mountain,  Sweetwater  County,  Wyoming,  Nelson  7058  (Gr,  NY,  UC); 
Cooper  Lake,  Albany  County,  Wyoming,  Goodding  21  (Gr,  NY,  UC,  US);  type  col- 
lection, Nuttall  (Gr,  Phila.). 

RELATIONSHIPS. 

The  shrubby  habit,  reduced  number  of  flowers,  narrow  disk-corollas,  and  the  cleft 
styles  of  the  disk-flowers  all  indicate  A.  pedatifida  as  an  ally  of  A.  fiUfolia,  notwithstand- 
ings  its  very  different  appearance.  It  is  the  high-altitude  and  northerly  representative 
of  that,  with  the  woody  portion  and  the  inflorescence  much  reduced.  Whether  either  of 
these  species  has  been  derived  from  the  other  can  not  be  stated  definitely,  for  intermediate 
forms  do  not  now  exist.  Notwithstanding  the  plainly  sterile  disk-flowers  A.  pedatifida 
was  originally  placed  in  the  section  Abrotanum,  presumably  through  an  oversight.  It  is 
in  no  way  connected  with  any  of  the  forms  of  that  group.  A  notable  peculiarity  of  the 
species  is  the  remarkable  length  of  the  disk-corollas,  these  averaging  about  twice  as  long 
as  those  of  other  and  much  larger  plants  of  the  same  section.  Because  of  its  low  stature, 
the  plant  is  sometimes  confused  with  A .  Iridentala  trifida,  but — aside  from  technical  char- 
acters such  as  the  sterile  disk-achenes  and  much  larger  and  broader  corollas — pedatifida 
may  be  distinguished  by  the  divergent  leaf-lobes,  the  larger  heads,  the  lower  of  which  are 
distinctly  peduncled,  and  by  the  gray  fibrous  bark  of  the  caudex  and  root. 

ECOLOGY  AND  USES. 

Artemisia  pedatifida  is  a  dwarf  shrubby  rosette-former,  resembling  A.  spinescens  and 
pygmaea  in  habit.  It  forms  the  characteristic  consocies  of  flat  alkaline  depressions  in 
Wyoming,  and  persists  for  a  long  time  in  the  succeeding  Agropyrum  consociation  of  the 
mixed  prairie.  It  is  an  indicator  of  the  presence  of  alkali  in  moderate  amounts.  In  the 
less  alkaline  associations  it  is  frequently  mixed  with  A.  frigida,  and  less  so  with  A. 
tridentata. 

The  foliage  of  this  Artemisia  is  doubtless  browsed  to  a  limited  extent  by  cattle  and 
sheep,  but  the  plants  are  too  small  to  be  compared  in  value  with  the  larger  sagebrushes. 
Since  also  the  species  is  of  limited  distribution,  its  economic  importance  is  apparently 
quite  negligible. 

24.  ARTEMISIA  SPINESCENS  D.  C.  Eaton,  in  Watson,  Bot.  King's  Expl.  180,  1871. 
Plate  17.    Bud  Sagebrush. 

A  rounded  spiny  shrub,  0.5  to  5  dm.  high,  with  a  strong  penetrating  odor  and  bitter 
taste;  stems  crowded,  much  branched  from  the  base,  thick  and  rigid,  the  older  parts 
with  a  brown  fibrous  bark,  the  twigs  ascending,  not  striate,  white-tomentose  or  short- 


A.   SPINESCENS.  .133 

villous;  principal  leaves  petioled,  flabellate  in  outline,  0.5  to  2  cm.  long  including  the  peti- 
ole, 0.5  to  1.5  cm.  wide,  pedately  3-  to  5-divided,  and  the  divisions  again  cleft  into  linear- 
spatulate  lobes,  densely  villous;  upper  leaves  similar  but  less  divided,  those  of  the  inflor- 
escence about  equaling  the  heads;  inflorescence  consisting  of  numerous  short  racemes  in 
the  axils  and  at  the  ends  of  the  short  branches,  sometimes  reduced  to  only  1  or  several 
heads,  leafy-bracted,  1  to  5  cm.  long,  0.5  to  1  cm.  broad,  the  persistent  rachis  transformed 
into  a  slender  rigid  spine  after  the  heads  have  fallen ;  heads  heterogamous,  short-pedun- 
cled  or  subsessile,  nodding;  involucre  broadly  turbinate,  2  to  3.5  mm.  high,  3  to  4.5  mm. 
broad;  bracts  4  to  8,  all  much  alike  and  scarcely  unequal,  obovate-cuneate  or  nearly  orbic- 
ular with  a  cuneate  base,  rather  thick  and  herbaceous,  with  narrow  scarious  margins, 
densely  villous ;  receptacle  naked ;  ray-flowers  2  to  6,  fertile,  corolla  very  slender,  about  1 
mm.  long,  2-  or  3-toothed,  long-hairy;  disk-flowers  5  to  13,  sterile,  corolla  funnelform 
with  narrow  tube,  5-toothed,  2  to  3  mm.  long,  copiously  clothed  with  long  flaccid  hairs 
except  on  the  limb ;  style  of  disk-flowers  undivided  at  the  expanded  and  radiately  penicil- 
late  summit,  included ;  achenes  of  ray-flowers  ellipsoid,  densely  arachnoid-hairy,  achenes 
of  disk-flowers  wanting.  {Picrothamnus  desertorum  Nuttall,  Trans.  Am.  Phil.  Soc.  II, 
7:417,  1841,  not  A.  desertorum  Sprengel,  Syst.  Veg.  3:490,  1825-28.) 

Common  on  arid  plains  and  slopes  from  Montana  and  Colorado  to  New  Mexico,  eastern 
California  (from  the  San  Bernardino  Mountains  north),  eastern  Oregon,  and  Idaho. 
Type  locaUty,  Rocky  Mountain  plains,  in  arid  deserts,  toward  the  north  sources  of  the 
Platte  River.  Collections:  Beaverhead  County,  Montana,  Tweedy  19  (according  to 
Rydberg,  Mem.  N.  Y.  Bot.  Card.  1:427,  1900);  Palisade,  western  Colorado,  May  29, 
1894,  Crandall  (NY);  Steamboat  Mountain,  Sweetwater  County,  Wyoming,  Nelson 
7047  (Gr,  NY,  UC);  Marysvale,  Utah,  Jones  5326  (NY,  UC,  US);  Navajo  Indian  Reser- 
vation, Arizona,  Standley  74-79  (US) ;  Rabbit  Springs,  north  base  San  Bernardino  Moun- 
tains, California,  April  25,  1915,  Shreve  (UC);  Truckee  Valley,  Nevada,  Kennedy  1966 
(UC);  Malheur  Butte,  eastern  Oregon,  Leiherg  2020  (UC,  US);  near  Pocatello,  Idaho, 
Palmer  14    (NY,    SF,    US). 

RELATIONSHIPS. 

Although  Picrothamnus  is  sometimes  taken  as  a  separate  monotypic  genus  because 
of  the  spiny  habit  and  notably  pubescent  flowers,  it  is  in  all  essentials  an  Artemisia  of 
the  section  Dracunculus.  The  only  differentiating  characters  are  those  of  habit  and  the 
pubescence  of  the  flowers,  as  has  been  already  indicated  (p.  33).  Its  nearest  relatives  are 
doubtless  species  of  central  Eurasia  that  do  not  extend  to  this  continent.  There  are, 
however,  two  cosmopolitan  species,  namely,  A.  dracunculus  and  A.  campestris,  with 
which  it  is  in  agreement  in  all  important  technical  characters  and  with  which  it  shares 
the  almost  unique  feature  of  a  tendency  towards  a  fusion  of  the  style-branches  of  the 
disk-flowers.  Whether  it  really  is  most  closely  connected  with  these  can  be  determined 
only  after  a  detailed  study  of  all  the  Old  World  Dracunculi.  Whatever  its  origin,  A. 
spinescens  is  now  sharply  set  off  from  all  other  species  both  morphologically  and  geo- 
graphically. No  other  American  species  approaches  it  in  its  spinescent  twigs,  although 
several,  especially  pygmaea,  pedatifida,  rigida,  and  the  dwarf  varieties  of  tridentata,  all 
but  one  members  of  another  section,  assume  a  dwarfed  and  rigid  habit  as  a  result  of 
similar  unfavorable  environments. 

The  degree  of  variation  in  involucre  and  floral  characters  is  indicated  by  table  12.  The 
most  striking  feature  here  brought  out  is  the  remarkably  low  variability,  indicating  a 
stable  non-plastic  species.  Even  the  small  differences  in  the  number  of  flowers  may  be 
due  to  the  falling-out  of  these  in  some  cases  where  the  count  runs  low.  Perhaps  it  is 
because  of  its  fixed  characters  and  consequent  incapacity  for  adaptation  to  new  environ- 
ments that  the  species  has  produced  no  forms  that  have  received  taxonomic  recognition. 


134 


GENUS   ARTEMISIA. 


ECOLOGY  AND  USES. 

Artemisia  spinescens  is  a  dwarf  shrubby  rosette-former,  suggesting  A.  pedatifida  and 
pygmaea  in  habit.  It  is  usually  found  in  a  mixed  consocies  of  the  sagebrush  climax  with 
other  halophytes,  and,  like  them,  is  an  indicator  of  considerable  alkali  in  the  soil. 

Notwithstanding  its  spiny  habit,  this  is  a  valuable  browse  plant  on  the  range,  especially 
in  Utah,  Nevada,  and  eastern  California,  where  it  is  known  to  stockmen  as  bud-sage. 
This  is  because  of  its  leafage,  which  develops  ahead  of  that  of  most  other  shrubs  in  the 
same  districts.  Its  chief  value  is  as  an  early  food  for  sheep.  Apparently  authentic 
cases  of  stock-poisoning  have  been  reported  for  this  species,  but  such  were  probably  due 
to  excessive  browsing  without  the  addition  of  other  foods.  Feeding  experiments  con- 
ducted by  Fleming  at  the  Nevada  Station  have  shown  that  the  plant  is  sometimes  but 
not  always  injurious  to  calves  and  that  sheep  are  perhaps  never  killed  by  it,  at  least  not 
in  the  presence  of  other  browse.  The  pollen  has  been  found  to  be  active  as  a  cause  of 
hay-fever  and  is  therefore  used  to  some  extent  for  preventing  this  disease  in  the  Great 
Basin  States. 


Table  12 

.—Variation 

in  Artemisia  s-pinescens. 

Herbarium. 

No.  of 

involucral 

bracts. 

No.  of 
ray-flowers. 

No.  of 
disk-flowers. 

Length  of 
disk-corolla. 

NY 

Gr 

NY 

Gr 

Gr 

146508  UC 

190180  UC 

193577  UC 

126503  UC 

5  6 

6  7 
5  5 

8 

7  5 

8  7 
4  4 

4  4 
4  4 
4  4 
4 
4  4 

4  4 

5  4 
5  6 

4 

8     7 
8     8 
8     8 
13 
8     5 
8     7 
8  12 
8  10 
8 

2.2 
2.3 
2.3 
2.4 
2.5 
2.2 
2.4 
2.4 
3.0 

Aztec   N    Mex               

Candelaria   Nev.               

Barstow  Calif 

' 

4 

8 

2.4 

Section  IV.  SERIPHIDIUM. 
Phylogeivy  of  the  Species. 
All  of  the  American  members  of  the  section  Seriphidium  are  shrubs,  this  habit  having 
been  developed  in  response  to  arid  climates.  There  is  at  present  no  obvious  connection 
with  any  of  the  herbaceous  species.  It  seems  that  such  connection  was  broken  very  early, 
perhaps  during  the  Pleistocene,  and  that  the  shrubby  Seriphidia  developed  in  the  south 
at  a  later  period.  Later  on,  during  the  dry  phase  following  the  Pleistocene,  they  appear 
to  have  moved  northward,  and  during  this  process  some  of  the  present-day  species  were 
doubtless  evolved.  This  hypothesis  very  nicely  accords  with  the  fact  that  the  most 
highly  modified  forms  now  occupy  the  most  northern  habitats.  If  the  American  mem- 
bers of  the  section  arose  independently  of  the  Old  World  species,  and  there  is  now  no 
obvious  connection  between  the  two  groups,  then  A.  bigelovi  is  to  be  considered  as  most 
closely  representing  the  primitive  stock.  This  has  been  universally  classified  in  the 
section  Ahrotanum,  because  of  the  presence  of  ray-flowers,  but  these  are  so  few,  or  even 
sometimes  wanting,  and  the  other  features  ally  it  so  closely  with  A.  tridentata  that  it  is 
taken  to  mark  the  borderland  between  the  two  sections.  For  this  reason  it  is  shown  on 
the  phylogenetic  chart  as  slightly  overlapping  the  Une  between  them.  Its  southern 
distribution  is  further  evidence  that  the  later  evolution  of  Seriphidium  has  been  associ- 
ated with  migrations  towards  the  north.  (See  the  account  further  on  of  the  relation- 
ships of  the  subspecies,  p.  141.) 


A.    TEIDENTATA. 


135 


Within  the  section  proper,  the  common  sagebrush  {A .  tridentata)  seems  to  be  the  most 
primitive,  largely  because  of  its  connection  as  just  mentioned  with  a  member  of  the 
obviously  lower  section  Abrotanum.  In  addition  to  6  subspecies  and  numerous  minor 
variations,  it  has  produced  3  distinct  species  along  the  northern  edge  of  its  distribu- 
tional area.  Of  these,  only  cana  is  at  all  common.  The  other  two,  rigida  and  pygmaea, 
evidently  are  adaptations  to  peculiar  and  exacting  conditions  in  the  Great  Basin  and 
the  districts  immediately  northward.    Both  exhibit  unusual  modifications  in  the  habit 


Fig.  19. —  Phylogenetic  chart  of  the  species  of  Artemisia  section  Seriphidium. 


and  cut  of  leaf  as  well  as  in  a  considerably  reduced  inflorescence.  A.  palmeri  is  so  unlike 
the  other  species  that  its  origin  is  extremely  doubtful.  It  is  indicated,  therefore,  on 
the  chart  as  arising  independently  near  the  base  of  the  group.  Further  data  upon 
which  this  outline  is  based  will  be  given  when  discussing  the  relationships  of  each  of 
the  species  mentioned. 

25.  ARTEMISIA  TRIDENTATA  Nuttall,  Trans.  Am.  Phil.  See.  11,  7:398,  1841.    Plates  18, 

19,  20.  Sagebrush. 
A  shrub,  typically  5  to  30  or  50  dm.  high  but  with  subspecies  only  1  to  5  dm.  high, 
aromatic  with  a  pungent  odor;  stems  erect,  with  usually  ascending  branches,  the  main 
one  commonly  trunk-like,  or  the  branches  spreading  and  depressed,  the  old  parts  with 
brown  or  nearly  black  shreddy  fibrous  bark,  the  twigs  gray  or  white  with  a  dense  but 
thin  and  fine  tomentum,  obscurely  striate;  principal  leaves  sessile  by  a  narrow  base 
or  apparently  petioled,  cuneate  or  flabelliform,  obtuse,  1  to  4  cm.  long,  2  to  5  mm. 


136  GENUS  ARTEMISIA. 

wide,  obtusely  3-toothed  (rarely  4-  to  7-toothed)  or  3-  to  5-cleft  or  parted  at  the  truncate 
summit,  canescent  or  silvery  with  a  very  fine  and  close  tomentum,  slightly  if  at  all 
viscid;  upper  leaves  linear  or  cuneate-linear,  mostly  entire,  acute,  pubescent  like  the 
lower  ones;  inflorescence  a  leafy-bracted  panicle,  this  commonly  diffusely  branched 
and  open,  then  10  to  25  cm.  long  by  2  to  10  cm.  broad,  but  sometimes  much  narrowed 
or  even  spike-like  and  only  0.5  to  2  cm.  broad;  heads  homogamous,  sessile,  erect,  or 
the  branches  of  the  inflorescence  sometimes  drooping,  usually  2  in  each  peduncled 
cluster;  involucre  ovoid  or  campanulate,  3  to  4.5  or  rarely  5  mm.  high,  1.8  to  3.5  or 
rarely  4  mm.  broad;  bracts  8  to  18,  the  outer  very  short  and  orbicular-ovate  or  occasion- 
ally narrowed  to  an  herbaceous  tip,  the  inner  elliptic-spatulate,  obtuse,  all  with  broad 
scarious  margin,  canescent  to  nearly  glabrous;  ray-flowers  wanting;  disk-flowers  3  to  12, 
or  in  subspecies  rothrocki  even  to  20,  fertile,  corolla  funnelform,  5-toothed,  2  to  3.3  mm. 
long,  resinous-glandular  especially  on  the  tube;  style-branches  flat,  enlarged  at  summit, 
where  the  margins  are  erose;  achenes  cylindric-turbinate,  the  summit  slightly  contracted 
or  broader  and  with  a  raised  border,  4-  or  5-angled  or  ribbed,  resinous-granuliferous, 
pubescent  only  in  subspecies  parishi. 

The  most  common  and  widely  distributed  shrub  of  western  North  America,  espe- 
cially on  arid  plains  of  the  Great  Basin,  but  ranging  to  timber-line  in  the  mountains; 
central  Montana  to  North  Dakota,  eastern  Colorado,  New  Mexico,  Lower  California, 
and  eastern  British  Columbia. 

SUBSPECIES. 
The  number  of  well-marked  variations  is  not  so  great  as  might  be  expected  in  a  plant 
of  such  wide  distribution.  This  may  be  due  to  an  inherent  lack  of  plasticity  or  it  may  be 
because  of  the  immense  abundance  and  nearly  continuous  distribution  over  most  of 
the  area  covered.  This  continuity  provides  for  copious  interbreeding  and  the  consequent 
swamping  of  most  variations  almost  as  rapidly  as  they  occur.  The  commonly  recognized 
variations,  which  are  more  or  less  fixed,  notwithstanding  the  influence  just  mentioned, 
are  provided  for  in  the  following  key,  and  their  characters  are  also  indicated  in  the 
diagram,  page  141.  Minor  additional  variations,  for  the  most  part  fluctuating  or  plainly 
ecologic,  are  of  course  numerous. 

Key  to  the  Subspecies  of  Artemisia  tridentata. 

Achenes  conspicuously  arachnoid-villous.     A  tall,  rare  shrub  of  southern  California  and 

western  Nevada (6)  parishi  (p.  137). 

Achenes  glabrous  or  only  resinous-granuliferous. 

Heads  1.5  to  2.5  mm.  broad,  with  usually  3  to  5  or  rarely  6  to  9  flowers;  inflorescence  spike- 
like to  diffusely  paniculate;  shrubs  either  low  or  tall. 

Inflorescence  1.5  to  7  cm.  broad,  loosely  paniculate;  shrubs  normally  tall (a)  typica  (p.  136). 

Inflorescence  only  0.5  to  2  or  rarely  3  cm.  broad,  narrowly  paniculate  or  spike-like; 
shrubs  often  low. 

Leaves  merely  3-toothed;  involucre  greenish  yellow (c)   nova  (p.  137). 

Leaves  in  part  cleft  into  linear  lobes  0.5  to  1  cm.  long;  involucre  canescent (d)  trifida  (p.  137). 

Heads  2.5  to  4.5  mm.  broad  with  6  to  20  or  rarely  only  5  flowers;  inflorescence  less  than 
3  cm.  broad,  often  spike-like;  shrubs  mostly  of  low  stature. 
Pubescence  gray  or  dull  white,  the  hairs  closely  appressed;  leaves  cuneate  or  spatulate 
in  outline. 

Leaves  mostly  1.5  cm.  or  less  long;  flowers  5  to  8 (e;   arbuscula  (p.  138). 

Leaves  1.5  to  3  cm.  long;  flowers  8  to  20,  rarely  6  or  7 (/}    rothrocki  (p.  138). 

I^ibescence  white,  loose  and  floccose;  leaves  narrowly  linear,  only  slightly  dilated  at 

summit  even  when  cleft " (g)   bolanderi  (p.  139) . 

25o.  Artemisia  tridentata  typica. — Shrub  normally  4  to  40  but  even  to  50  dm. 
high,  sometimes  reduced  to  1  dm.  under  unfavorable  conditions,  usually  with  definite 
trunk  or  several  ascending  trunk-like  branches;  leaves  narrowly  cuneate,  1.5  to  4  cm.  long, 
3-toothed  (rarely  4-  to  7-toothed)  at  the  apex  or  the  uppermost  linear  or  oblanceolate 
and  entire;  inflorescence  openly  paniculate,  1.5  to  10  cm.  broad;  heads  ovoid,  about  2 
to  2.5  mm.  broad;  involucre  canescent;  flowers  4  to  6;  corolla  2  to  2.5  mm.  long;  achenes 


A.    TRIDENTATA.  137 

resinous-granuliferous.  {A.  tridentata  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:398,  1841.) 
Montana  to  western  Dakotas,  New  Mexico,  Lower  California,  Washington,  and  British 
Columbia,  by  far  the  most  abundant  form  over  all  this  region.  Type  locality,  plains  of 
the  Columbia  River.  Collections:  Near  Glendive,  Montana,  Sandberg  1010  (Gr,  NY, 
US);  Laramie  Hills,  Wyoming,  Nelson  53S5  (UC);  near  Dulce,  New  Mexico,  Standley 
8107  (US);  Navajo  to  Hawthorn,  Arizona,  Griffiths  5798  (US);  east  of  Ensenada,  Lower 
California,  Goldman  1117  (US);  San  Pedro  Martir,  Lower  California,  May  6,  1893, 
Brandegee  (UC) ;  Alamo  Mountain,  Ventura  County,  California,  Baldwin  104  (UC); 
Butte  Valley,  Siskiyou  County,  California,  Butler  1883  (UC,  US);  Steins  Mountains, 
Nevada,  Griffiths  and  Morris  656  (NY,  US);  type  collection,  "plains  of  the  Columbia 
and  Lewis  River,"  Nuttall  (Gr),  also  "Rocky  Mountains  and  Lewis  River,"  Nuttall 
(Phila.);  eastern  Oregon,  Cusick  2505  (Gr,  NY,  UC,  US);  Bingen,  Klickitat  County, 
Washington,  Suksdorf  2687  (Gr,  US);  Kamloops,  British  Columbia,  July  28,  1890, 
Macoun  (NY,  US);  Big  Butte  Station,  Idaho,  Palmer  498  (US). 

256.  Artemisia  tridentata  parishi  (Gray). — Shrub  normally  10  to  20  dm.  high, 
erect,  with  ascending  branches,  the  main  ones  trunk-like ;  leaves  spatulate  (usually  very 
narrowly  so)  or  linear,  2  to  3  cm.  long,  mostly  entire  but  some  obtusely  2-  or  3-toothed 
at  the  summit;  inflorescence  openly  paniculate,  2  to  10  cm.  broad  (much  condensed 
in  unfavorable  seasons);  heads  narrowly  campanulate,  2.2  to  3  mm.  broad;  involucre 
canescent;  flowers  4  to  6;  corolla  2  to  2.5  mm.  long;  achenes  glandular  and  also  short- 
villous  with  crisp  hairs  or  these  sometimes  longer  and  arachnoid.  {A.  parishi  Gray, 
Proc.  Am.  Acad.  17:220,  1882.)  Southwestern  part  of  the  Mojave  Desert,  California, 
extending  to  the  coastal  slope  along  the  Santa  Clara  River,  also  in  western  Nevada.' 
Type  locality,  Newhall,  Los  Angeles  County,  California.  Collections  (all  in  California 
except  the  last):  Near  Rosamond,  Antelope  Valley,  Davy  2933  (UC);  2  km.  west  of 
Rosamond,  Hall  10959;  type  collection,  1881,  Parish  1065  (Gr,  NY,  UC,  US);  dry  valley 
bottom  at  junction  of  Piru  Creek  and  Santa  Clara  River,  Ventura  County,  October  20, 
1919,  Hall  (UC);  Carson  Sink  Region,  west  central  Nevada,  Kennedy  1692  (DS,  NY, 
UC  at  least  as  to  flowering  specimens). 

25c.  Artemisia  tridentata  nova  (Nelson). — Shrub  1  to  3  dm.  high,  with  numerous 
erect  slender  branches  from  a  spreading  base;  leaves  cuneate  or  broader,  0.5  to  1.5  cm. 
long,  3-toothed  at  the  apex,  or  the  upper  ones  (toward  summit  of  inflorescence)  linear 
and  entire;  inflorescence  a  narrow  but  open  panicle,  0.5  to  1.5  cm.  broad;  heads  ovoid, 
about  2  mm.  broad;  involucre  greenish-yellow  and  nearly  glabrous,  except  for  the  short 
outer  canescent  bracts ;  flowers  3  to  6 ;  corolla  2  to  2.5  or  3  mm.  long ;  achenes  resinous.  {A . 
nova  Nelson,  Bull.  Torr.  Club  27:274,  1900.)  Idaho,  Montana,  and  western  Colorado 
to  New  Mexico,  Arizona,  and  eastern  California,  especially  on  hillsides  and  ridges  of 
plateaus  and  desert  mountains.  Tj-pe  locality,  Medicine  Bow,  Wyoming.  Collections: 
Midway  between  Strevell  and  Albion,  southern  Idaho,  September,  1919,  Hall  (CI); 
near  Radersburg,  Montana,  August  27,  1882,  Canby  (Gr);  Laramie  Hills,  Wyoming, 
Nelson  5334  (Gr,  NY,  UC);  Gunnison,  Colorado,  Underwood  and  Selby  4OO  (US); 
Panguitch  Lake,  Utah,  Jones  5997  (NY,  UC,  US);  near  Dulce,  New  Mexico,  Standley 
8099  (US) ;  mesa  west  of  Buckskin  Mountains,  Arizona,  Jones  6063F  (NY,  UC) ;  Mount 
Irish,  Nevada,  Purpus  6333  (UC,  US);  Silver  Canon,  Inyo  Range,  California,  Hall 
10639  (UC). 

25d.  Artemisia  tridentata  trifida  (Nuttall). — Shrub  2  to  6  dm.  high  (perhaps 
sometimes  much  higher),  usually  with  erect  trunk-like  main  stems;  leaves  cuneate  or 
flabelliform,  1.5  to  4  cm.  long,  deeply  3-cleft  into  linear  or  linear-oblanceolate  divisions 

'  Reported  in  the  original  description  as  occurring  also  in  Cajon  Pass,  California,  but  this  was  an  error  (Pariah,  Zoe 
6: 120,  1901). 


138  GENUS   ARTEMISIA. 

which  are  themselves  3-cleft,  or  the  uppermost  ones  linear  and  entire;  inflorescence 
loosely  paniculate,  1  to  3  cm.  broad;  heads  ovoid,  2.5  mm.  or  less  broad;  involucre 
canescent;  flowers  5  to  8;  corolla  2  to  2.5  mm.  long;  achenes  resinous-granuliferous. 
(A.  irifida  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:398,  1841.)  Northern  Rocky  Mountain 
and  Great  Basin  States,  on  open  plains;  Montana  to  Colorado  and  west  to  eastern  Oregon 
and  Washington,  apparently  also  in  eastern  California  and  reported  from  British  Colum- 
bia. Type  locality,  plains  of  the  Rocky  Mountains.  Collections:  Type  collection, 
Nuttall  (Phila,  with  a  piece  of  A.  rigida);  Alaska  Basin,  Montana,  Nelson  6809  (Gr, 
NY,  US);  Big  Butte  Station,  Idaho,  Palmer  497  (US);  Teton  Forest,  northwestern 
Wyoming,  Tweedy  668  (NY);  Laramie  Plateau,  Wyoming,  September  9,  1919,  Hall 
(UC);  near  Lancaster,  Mojave  Desert,  California,  Parish  1177  (identical  with  Nuttall's 
plants,  according  to  Gray);  eastern  Oregon,  Cusick  2501  (Gr,  NY,  UC,  US);  base  of 
Cascade  Mountains,  Washington,  1882,  Brandegee  (UC). 

25e.  Artemisia  tridentata  arbuscula  (Nuttall). — Shrub  1  to  4  dm.  high,  stiffly 
and  irregularly  much  branched,  the  lower  branches  spreading  and  often  spinescent,  the 
twigs  slender  and  erect;  pubescence  gray,  appressed;  leaves  cuneate  or  flabelliform, 
mostly  1.5  cm.  or  less  long,  3-  to  5-lobed  or  cleft  at  apex,  the  lobes  sometimes  10  mm. 
long,  the  uppermost  entire;  inflorescence  spike-like,  L5  cm.  or  less  broad;  heads  campanu- 
late,  2.5  to  3  mm.  broad;  involucre  canescent;  flowers  5  to  9;  corolla  2  to  nearly  3  mm. 
long;  achenes  granuliferous.  (A.  arbuscula  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:398, 
1841,  in  part,  the  remainder  being  subspecies  nova.)  Northern  Rocky  Mountains  and 
Great  Basin,  on  dry,  rocky  hillsides  and  plains,  especially  on  the  scab-lands;  Idaho, 
Wyoming,  and  western  Colorado  to  eastern  California  and  Washington.  Type  locality, 
arid  plains  of  the  Snake  River.  Collections:  Type  collection,  Nuttall  (Gr,  Phila.;  the 
specimen  at  Philadelphia  is  a  young  plant  with  racemose  inflorescence,  the  involucres  very 
tomentose,  and  the  whole  appearance  that  of  arbuscula  as  here  described  rather  than  of 
nom);  near  Evanston,  Wyoming,  September  12,  1919,  Hall;  Hayden  Flats,  Routt  County, 
Colorado,  Osterhout  2260  (NY);  Mount  Rose,  western  Nevada,  Heller  9883  (DS,  Gr); 
near  Olancha  Peak,  southern  Sierra  Nevada,  California,  Purpus  1868  (UC);  Mono 
County,  California,  August,  1898,  Congdon  (UC);  ridge  northwest  of  Donner  Pass, 
California,  Heller  12914  (Gr,  SF,  UC,  US,  see  minor  variation  9);  divide  between 
American  and  Rubicon  Rivers,  Eldorado  County,  California,  Kennedy  203  (UC);  near 
Hay  Creek,  eastern  Oregon,  Leiberg  859  (DS,  Gr,  UC,  US) ;  Yakima  region,  Washington, 
Brandegee  I46  (UC). 

25/.  Artemisia  tridentata  rothrocki  (Gray). — Shrub  1  to  8  dm.  high,  or  perhaps 
more,  branching  from  the  base  to  form  low  rounded  bushes  with  erect  twigs,  not  espe- 
cially rigid;  pubescence  gray,  appressed,  sometimes  viscidulous ;  leaves  elongate-cuneate, 
1  to  4  cm.  long,  3-toothed  at  apex,  or  3-cleft  and  the  lobes  toothed,  many  of  the  upper 
or  even  some  below  the  inflorescence  linear  and  entire;  inflorescence  spike-like  or  very 
narrowly  paniculate,  1  to  3  cm.  broad;  heads  campanulate,  3  to  4.5  or  rarely  5  mm. 
broad ;  involucre  varying  from  greenish-yellow  or  straw-color  and  only  obscurely  tomentu- 
lose  as  in  the  original  rothrocki,  to  closely  canescent  (minor  variation  7,  A.  spiciformis 
Osterhout),  somewhat  viscidulous  in  the  green  form  (outer  bracts  broadly  ovate  and 
canescent,  inner  ones  broadly  elliptic  and  scarious  in  minor  variation  18,  .4.  vaseyana 
Rydberg) ;  flowers  6  to  15,  rarely  to  20;  corolla  2.5  to  3.5  mm.  long;  achenes  only  granular. 
(A.  rothrocki  Gray,  Bot.  Calif.  1:618,  1876.)  Widely  distributed  in  the  western  United 
States  but  wanting  over  much  of  the  area,  confined  to  the  higher  zones  in  the  mountains: 
Rocky  Mountains  of  Wyoming,  Colorado,  and  Utah;  San  Bernardino  Mountains  of 
southern  California;  Olancha  Peak,  in  the  southern  Sierra  Nevada  of  California,  to 
eastern  Washington,  western  Nevada,  and  Idaho.     Type  locality,  Sierra  Nevada  of 


A.   TRIDENTATA.  139 

Tulare  County,  California,  Olancha  Mountains  and  Monache  Meadows.  Collections 
(those  from  Utah  and  east  chiefly  of  minor  variation  7,  that  is  A.  spiciformis  Osterhout): 
Cooper  Hill,  Albany  County,  Wyoming,  Nelson  8941a  (UC) ;  North  Park,  Colorado, 
Osterhout  2255  (NY,  UC,  topotype  of  A.  spiciformis  Osterhout,  minor  variation  7); 
Minturn  to  Leadville,  Colorado,  Hall,  11064,  11055,  11057  (UC);  Crested  Butte,  west 
central  Colorado,  Baker  810  (Gr,  NY,  UC,  US);  Aquarius  Plateau,  Utah,  Ward  593 
(Gr);  head  of  Pass  Canon,  Tooele,  Utah,  August  9,  1913,  Blankinship  (hb.  Blankinship) ; 
California:  east  end  of  Bear  Lake,  San  Bernardino  Mountains,  Bailey  1244  (UC);  type 
collection,  in  part,  Monache  Meadows,  at  2,200  meters  altitude,  September,  1875, 
Rothrock  298  (Gr,  US) ;  type  collection,  remainder,  Olancha  Peak,  at  2,870  meters  alti- 
tude, September,  1875,  Rothrock  343  (Gr,  Phila,  US) ;  Little  Cottonwood  Creek,  Inyo 
County,  September  6,  1911,  California  Museum  of  Vertebrate  Zoology  (UC);  near 
Soda  Creek,  southern  Sierra  Nevada,  Purpus  5165  (UC,  US) ;  Volcano  Meadows,  Tulare 
County,  Hall  and  Babcock  5490  (UC) ;  Soda  Springs  of  the  Tuolumne,  August  22,  1894, 
Congdon  (UC);  Mono  Pass,  August  13,  1898,  Congdon  (Gr,  UC);  Mount  Dana,  Bolander 
6018  (UC,  US);  Tioga  Pass,  Hall  10847  (UC);  Ebbets  Pass,  Brewer  1996  (UC);  Angora 
Peak,  near  Tahoe,  Smiley  20  (Gr);  Bear  Valley,  on  Truckee  River,  Placer  County, 
September  9,  1888,  Sonne  (NY,  UC,  leaves  from  merely  dentate  to  cleft  into  lobes  up 
to  10  mm.  long) ;  Webber  Lake,  August,  1878,  Lemmon  (Gr) ;  south  side  of  Slide  Mountain, 
Washoe  County,  Nevada,  Heller  10667  (NY);  Hurricane  Creek,  Wallowa  Mountains, 
Oregon,  Cusick  2486  (NY,  UC,  US);  Washington,  Vasey  480  (NY,  type  of  A.  vaseyana 
Rydberg,  minor  variation  18);  Yakima  Region  Washington,  Brandegee  910  (UC); 
Ketchum,  Blaine  County,  Idaho,  Nelson  and  Macbride  1190  (UC,  US). 

25g.  Artemisia  tridentata  bolanderi  (Gray). — Shrub  2  to  6  dm.  high,  branching 
to  form  low  bushes  with  erect  densely  leafy  twigs,  not  rigid  or  at  all  spinose ;  pubescence 
white,  loose  and  floccose;  leaves  mostly  narrowly  linear  and  entire  but  many  dilated 
at  apex,  where  cleft  into  3  narrow  lobes  (see  fig.  22d,  p.  145),  1  to  2  cm.  long  or  perhaps 
longer;  inflorescence  varying  from  spike-like  and  less  than  1  cm.  broad  to  narrowly 
paniculate  and  3  cm.  broad;  heads  campanulate,  2.5  to  3  mm.  broad;  involucre  loosely 
white-canescent;  flowers  8  to  15;  corolla  2  to  2.5  mm.  long;  achenes  granuliferous. 
(A.  bolanderi  Gray,  Proc.  Am.  Acad.  19:50,  1883.)  Known  only  from  Mono  county, 
California.  Type  locality.  Mono  Pass  in  the  Sierra  Nevada.  Collections:  Type  col- 
lection, Bolander  6149  (Gr,  UC,  US);  Sand  Flat,  south  of  Mono  Lake,  California, 
Clements  and  Hall  11702  (UC);  between  Walker  and  Mono  Lakes,  California,  August  6, 
1898,  Congdon  (DS). 

MINOR  VARIATIONS  AND  SYNONYMS. 

A  tabulation  of  the  characters  of  the  subspecies  and  of  most  of  the  following  forms  is 
given  in  table  13.  From  this  it  is  seen  that  the  taxonomic  recognition  of  all  possible 
combinations  of  characters  would  result  in  a  classification  too  cumbersome  for  general 
use.  The  more  important  variations  not  already  provided  for  as  subspecies  are  the 
following: 

1.  Artemisia  angusta  Rydberg,  N.  Am.  Fl.  34:283,  1916. — Based  upon  A.  tridentata  angustijolia,  which  see. 

2.  A.  ARBUSCULA  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:398,  1841. — A.  tridentata  arbuscula  and  A.  t.  nova. 

3.  A.  BOLANDERI  Gray,  Proc.  Am.  Acad.  19:50,  1883.— A.  tridentata  bolanderi. 

4.  A.  NOVA  Nelson,  Bull.  Torr.  Club  27:274,  1900.— A.  tridentata  nova. 

5.  A.  PARisHi  Gray,  1.  c.  17:220,  1882.— A.  tridentata  parishi. 

6.  A.  ROTHROCKi  Gray,  Bot.  Calif.  1:618,  1876.— A.  tridentata  rothrocki. 

7.  A.  SPICIFORMIS  Osterhout,  Bull.  Torr.  Club  27:507,  1900. — A.  tridentata  rothrocki.  The  original  speci- 
mens, from  North  Park,  Colorado,  are  more  densely  cinereous  than  the  originab  of  rothrocki  from  the  southern 
Sierra  Nevada,  and  the  latter  are  somewhat  viscid.  Colorado  plants  are  generally  of  a  decided  gray  or  whitish 
color,  due  to  the  dense  pubescence,  but  in  a  collection  from  near  Leadville  (//oii  11057)  the  lower  leaves  are  as 


140  GENTJS  ARTEMISIA. 

green  as  in  specimens  from  the  type  locality  of  rothrocki,  and  in  one  from  Crested  Butte,  Colorado  {Baker  810) 
the  involucres  are  essentially  glabrous,  except  for  the  short  outer  bracts.  In  the  former  collection  the  (young) 
involucres  are  gray-tomentose,  in  the  latter  the  foUage  is  densely  cinereous.  These  perplexing  combinations, 
together  with  the  fact  that  Sierra  Nevadan  plants  are  for  the  most  part  decidedly  cinereous-canescent  and 
scarcely  viscidulous,  render  impossible  the  recognition  of  spidjormis.     (See  further  under  No.  18  of  this  list.) 

8.  A.  6PICIF0RMI8  var.  lonqiloba  Osterhout,  Muhlenbergia  4:69,  1908. — A  low  form  of  A.  tridentata  roth- 
rocki with  densely  canescent  foliage,  the  leaves  3-cleft  for  nearly  one-half  their  length.  Plants  about  3  dm.  high. 
Scarcely  differs  from  subspecies  trifida,  except  in  size  of  head  and  number  of  flowers.  Type  locality,  Sulphur 
Springs,  Colorado. 

9.  A.  TRIDENTATA  ANG0STIFOLIA  Gray,  Proc.  Am.  Acad.  19:49,  1883.— A  narrow-leaved  form  of  A.  triden- 
tata  typica.  Lower  leaves  spatulate-linear  and  scarcely  3-toothed  at  the  rounded  apex;  upper  entire  and  linear. 
Original  distribution  given  as  southern  Idaho  and  western  Nevada  to  the  Mojave  Desert  and  the  southern 
borders  of  California. 

10.  A.  TRIDENTATA  ARBUSCULA,  but  with  the  Icaves  deeply  cleft  as  in  No.  8  of  this  list  and  in  subspecies 
trifida.     Best  represented  by  plants  from  Placer  County,  California,  Heller  1S914  (UC). 

11.  A.  TRIDENTATA  NOVA,  but  the  involucrcs  canescently  tomentulose  and  the  stem  commonly  reddish.  It 
seems  better  to  accept  this  as  a  minor  variation  of  subspecies  nova  rather  than  to  give  it  subspecific  rank,  partly 
because  of  the  presence  of  intergrading  forms  (Mount  Irish,  Nevada,  Purpus  6333  UC),  partly  because  the  short 
outer  bracts  are  always  canescent  even  in  genuine  nova,  and  partly  because  of  the  demonstrated  variability  of 
this  character  in  related  subspecies,  for  example  rothrocki.  This  form  sometimes  forms  pure  stands  in  eastern 
California  and  eastern  Oregon  in  regions  where  the  surrounding  vegetation  is  composed  chiefly  of  subspecies 
typica.  The  line  between  the  two  is  often  very  sharp,  the  low  reddish-twigged  nova-V\ke  plant  occupying  the  less 
favorable  locations  and  persisting  because  of  repeated  fires  or  grazing,  if  not  actually  produced  by  them.  Typi- 
cal of  this  form  is  a  collection  from  between  Bodie  and  Bridgeport,  Mono  County,  California,  August  18,  1898, 
Congdon  (UC).  It  is  common  on  upper  slopes  between  Mono  Lake  and  Bridgeport  {Hall  11696,  UC).  Also  in 
eastern  Lassen  County,  California  {Hall  11674,  UC)  and  in  eastern  Oregon  (near  Antone,  Lofifield  2113,  UC). 
Almost  the  same  thing,  but  the  slender  inflorescences  more  branched,  comes  from  draws  south  of  Laramie, 
Wyoming  (September  9,  1919,  Hall,  UC). 

12.  A.  TRIDENTATA  NOVA,  but  with  dark  foliage,  this  appearing  almost  black  as  compared  with  other  forms. 
Plants  low  and  with  narrow  inflorescences.  Apparently  a  more  palatable  strain  kept  low  by  grazing.  Occurs 
in  southern  Idaho  and  elsewhere. 

13.  A.  TRIDENTATA  ROTHROCKI,  but  somc  of  the  leaves  cleft  one-third  their  length.  Volcano  Meadows, 
southern  Sierra  Nevada,  Hall  and  Babcock  5490  (UC). 

14.  A.  TRIDENTATA  TYPICA,  but  with  the  branches  of  the  inflorescence  drooping.  The  best  examples  are 
large  shrubs  growing  in  moist,  sandy  soil.  Found  especially  in  northwestern  New  Mexico  {Hall  11124).  Well 
worthy  of  cultivation  as  an  oranmental  shrub  if  the  character  persists. 

15.  A.  TRIDENTATA  TYPICA,  but  much  dwarfed,  usually  as  a  result  of  competition  with  grasses.  Resembles 
subspecies  nova  in  its  stature,  but  lacks  its  slender  habit,  narrow  inflorescence,  and  smooth  involucres.  Common 
in  Wyoming,  for  example,  west  of  Bosler,  September  10,  1919,  Clements  (UC). 

16.  A.  TRIFIDA  Nuttall,  Trans.  Am.  PhU.  Soc.  II,  7:398,  1841.— A.  tridentata  trifida. 

17.  A.  TRIPARTITA  Rydberg,  Mem.  N.  Y.  Hot.  Card.  1:432,  1900.— Based  upon  .4.  trifida  Nuttall,  here 
reduced  to  a  subspecies  of  A.  tridentata.  The  specific  name  was  changed  by  Rydberg  because  of  the  earlier 
A.  trifida  Turczaninov,  1832,  an  untenable  species. 

18.  A.  VASEYANA  Rydberg,  N.  Am.  Fl.  34:283,  1916.— A.  tridentata  rothrocki.  Separated  by  Rydberg 
chiefly  on  its  broadly  ovate  outer  bracts,  which  are  less  than  half  as  long  as  the  innermost,  rothrocki  being 
described  as  having  one  of  the  outer  bracts  often  a  little  foliaceous,  the  others  ovate,  acute,  and  half  as  long  as 
the  innermost.  The  slight  herbaceous  elongation  of  outermost  bracts  is  common  in  all  of  the  subspecies  and  is 
so  variable  as  to  suggest  a  correlation  with  factors  affecting  growth.  A  careful  comparison  has  been  made 
between  the  types  of  the  two  "species."  If  the  outer  bracts  are  broader  and  more  obtuse  in  vaseyana,  they  are 
not  convincingly  so  and  they  are  no  shorter  in  proportion  to  the  inner  ones.  They  are  quite  canescent  as 
contrasted  with  the  nearly  glabrous  bracts  of  the  type  of  rothrocki,  but  the  lack  of  constancy  in  this  feature  has 
been  pointed  out  under  A.  spiciformis.  Its  use  would  necessitate  the  extension  of  the  range  of  vaseyana  to  the 
type  locality  of  rothrocki  (Univ.  Calif.  Herb.  202229).  The  number  of  flowers  in  the  head  and  the  height  of  the 
involucre  do  not  serve,  as  is  shown  in  Table  14,  where  the  type  of  vaseyana  and  other  specimens  from  its  region 
are  entered.  It  would  seem,  therefore,  that  if  vaseyana  can  be  recognized  at  all,  it  must  be  on  its  canescent  and 
slightly  broader  outer  bracts,  and,  if  further  collections  substantiate  the  measurements  given  in  the  table,  on 
its  narrower  heads.  Even  as  thus  defined,  the  range  must  be  extended  to  include  most  of  the  Sierra  Nevada, 
and  here  spiciformis  must  also  be  admitted,  because  of  plants  with  acutish  but  decidedly  canescent  bracts  (for 
example.  Bear  Valley,  on  road  to  Tahoe,  September  9,  1888,  Sonne).  It  is  thus  seen  that  these  forms  can  not 
be  correlated  with  geographic  distribution,  except  that  genuine  rothrocki  is  closely  confined  to  the  vicinity  of  its 
type  locality.    The  type  locality  of  vaseyana  is  Washington. 


A.    TRIDENTATA. 


141 


RELATIONSHIPS. 
The  considerable  number  of  herbaceous  species  of  Artemisia  common  to  Eurasia  and 
North  America  justifies  the  assumption  that  it  is  a  boreal  genus  which  has  extended  far 
southward.  This  migration  brought  it  into  regions  with  climates  growing  drier  as  a 
consequence  of  the  action  of  climatic  cycles,  and  led  to  the  evolution  of  two  new  ecological 
groups  of  species.  The  one  was  characterized  by  the  assumption  of  the  shrub  habit  in 
response  to  arid  climates,  while  the  other  was  marked  by  halophytic  adaptation  to  local 
saline  areas,  usually  in  the  form  of  a  half-shrub.  It  seems  probable  that  Artemisia 
tridentata  was  one  of  the  first  shrubby  species  to  be  developed  in  response  to  climatic 


Phylogenetic  chart  of  the  subspeciea  of  Artemisia  tridentata. 


aridity  in  the  southwestern  United  States  and  in  Mexico.  During  the  dry  phase  fol- 
lowing the  Pleistocene  it  appears  to  have  moved  northward,  occupying  the  southern 
half  of  the  Great  Basin  as  the  great  dominant  and  extending  northward  into  Idaho, 
Wyoming,  Oregon,  and  Washington  to  form  a  low  savannah  in  the  bunch-grass  and 
mixed  prairies.  With  the  beginning  of  the  historical  period,  grazing  gradually  eliminated 
the  grasses,  and  the  sagebrush  increased  correspondingly,  until  much  of  the  savannah 
was  converted  into  a  pure  sagebrush  community. 

The  phylogenetic  origin  of  A.  tridentata  is  connected  with  the  evolution  of  the  section 
to  which  it  belongs,  namely,  Seriphidium.  It  has  been  shown  in  the  introduction  that 
this  is  one  of  the  most  highly  developed  sections,  that  it  is  a  derivative  of  the  section 


142  GENUS  AHTEMISIA. 

Abrotanum,  and  that  the  connection  is  represented  in  America  by  A.  bigelovi,  a  rare 
southern  species  of  the  latter  group.  On  the  Seriphidium  side  of  the  line,  the  nearest 
approach  to  bigelovi  is  found  in  A.  tridentata.  Except  in  the  character  indicative  of  the ' 
section,  the  two  species  are  so  nearly  alike  that  they  are  frequently  mistaken  for  each 
other.  Of  especial  significance,  as  indicating  their  phyletic  connection,  is  the  occurrence 
in  each  of  the  unique  tridentate  character  of  the  leaves.  This  occurs  nowhere  else  in 
the  genus  and  certainly  its  appearance  in  these  two  species,  so  closely  similar  in  most 
other  characters,  is  more  than  a  coincidence.  The  conclusion  therefore  is  that,  since 
the  section  Seriphidium  is  derived  from  Abrotanum  and  the  connection  is  best  represented 
on  the  side  of  the  former  by  the  species  tridentata,  this  species  inevitably  must  be  con- 
sidered as  the  most  primitive  of  the  group  to  which  it  belongs.  Its  connections  with 
the  other  members  of  the  section  will  be  taken  up  as  these  are  reached. 

In  considering  the  subspecies  of  A.  tridentata  an  annoying  nomenclatorial  difficulty  is 
encountered.  It  so  happens  that,  if  the  rule  of  priority  is  extended  to  include  position 
on  the  page,  the  name  of  the  species  must  be  changed  to  A.  trifida  Nuttall  and  the  com- 
bination of  each  subspecies  must  be  changed  to  correspond.  This  follows  from  the  fact 
that  trifida  and  tridentata  were  first  published  on  the  same  page  (Trans.  Am.  Phil.  Soc.  II, 
7:398,  1841)  and  that  the  description  of  the  former  precedes  that  of  the  latter.  But 
still  another  name  must  be  chosen  by  those  who  adhere  to  the  American  Rules  (and  they 
are  the  only  ones  strictly  bound  to  follow  the  rule  of  priority  of  position),  for  Nuttall's 
A.  trifida  is  antedated  by  A.  trifida  Turczaninov  (Bull.  Soc.  Nat.  Mosc.  5:196,  1832), 
a  species  now  universally  considered  as  belonging  to  Tanacetum.  The  first  available 
name  under  these  rules  would  be  A.  arbuscula,  since  this  was  published  by  Nuttall 
on  the  same  page  as  trifida  and  tridentata  and  placed  so  as  to  follow  the  former  but  to 
precede  the  latter.  It  is  partly  because  of  these  several  possible  applications  of  the  rules 
with  the  inevitable  shifting  of  names  that  the  International  Code  is  here  followed  and 
no  attention  paid  to  priority  of  position.  By  this  method  a  choice  is  allowed  between 
arbuscula,  trifida,  and  tridentata  as  the  name  for  the  collective  species.  Since  the  form 
described  by  Nuttall  as  A.  tridentata  is  by  far  the  most  common  and  widespread  and 
since  this  name  is  much  better  known  than  either  of  the  others,  it  is  here  selected.  In 
the  narrow  original  sense  A.  tridentata  Nuttall  here  becomes  A.  tridentata  typica. 

Of  all  the  subspecies  of  A.  tridentata  perhaps  none  comes  nearer  to  representing  the 
ancestral  type  than  does  typica  itself.  This  conclusion  follows  not  so  much  because  of 
its  great  abundance  over  large  areas  of  territory,  as  because  of  its  obvious  connection  with 
A.  bigelovi,  which  in  turn  represents  the  still  more  primitive  group  from  which  the  species 
probably  has  arisen.  No  other  is  so  much  like  bigelovi  in  habit,  foliage,  and  involucre. 
Furthermore,  each  of  the  other  subspecies  exhibits  characters  or  distributional  pecu- 
liarities indicative  of  more  recently  derived  forms.  As  is  so  often  the  case  when  dealing 
with  small  taxonomic  units,  the  subspecific  characters  are  found  to  group  themselves 
into  a  bewildering  array  of  combinations,  so  that  one  is  perplexed  to  know  which  forms 
to  accept  as  of  this  rank.  Previous  treatments  have  merely  selected  the  more  striking 
variations  and  assigned  to  them  either  specific  or  varietal  standing.  As  a  method  this 
can  scarcely  be  improved  upon,  since  a  recognition  of  all  of  the  combinations  of  minute 
characters  is  obviously  impracticable.  It  should  be  pointed  out,  however,  that  the 
number  of  possible  combinations  is  exceedingly  great  and  these  are  becoming  more  and 
more  numerous  in  herbaria  as  the  result  of  more  extended  collections.  This  is  one  reason 
for  bringing  all  of  the  7  subspecies  here  described  into  one  species,  although  some  of  them 
have  not  been  heretofore  considered  as  a  part  of  A.  tridentata.  The  various  combina- 
tions that  have  thus  far  received  names,  as  well  as  some  that  have  not,  are  indicated  in 
table  13,  which,  however,  does  not  include  all  of  the  minor  peculiarities  of  some  of  the 
forms.    The  subspecies  parishi  is  omitted,  since  it  differs  from  all  others  by  a  constant 


A.   TRIDENTATA. 


143 


character.  Its  inclusion  would  introduce  a  new  series  of  combinations,  with  the  addi- 
tional characters  of  pubescence  of  achene,  drooping  of  thie  inflorescence,  and  width  of 
leaf. 

Some  of  the  tabulated  forms  exhibit  additional  divergent  features.  Since  these  may 
be  expected  in  each  of  the  other  forms,  the  total  number  of  possible  combinations 
becomes  so  great  that  no  practicable  system  of  nomenclature  can  provide  for  them. 
Such  features  include  drooping  inflorescences,  reduced  number  of  flowers,  dark  foliage 
associated  with  low  stature  and  narrow  inflorescence,  density  of  pubescence,  color  and 
looseness  of  pubescence  (see  subspecies  bolanderi),  and  relative  lengths  of  inner  and 
outer  bracts  of  the  involucre. 

Table  13. — Character  combinations  found  in  Artemisia  Iridentata. 


Habit. 

Leaves. 

Inflorescence. 

Heads. 

Involucre. 

Subspecies  or 
minor  variation. 

Tall 

3-toothed 

Broad 

subsp.  Ivpica. 
m.  V.  15. 

subsp.  nova. 
subsp.  trifida. 
m.  V.  7. 
m.  V.  8. 

subsp.  arbuscula. 
m.  V.  10. 
subsp.  Tothrocki. 
m.  V.  13. 

Low 

Do 

Do 

Low     

Do    .    .    . 

Do 

Low 

Do 

Do 

Do 

Greenish 

Low 

Tall 

3-toothed 

3-cIeft 

Do 

Do 

Large 

Do 

Low.    . 

Do 

Do 

Low 

3-lobed 

Do 

Low 

Tall  or  low 

3-cleft  

Do   .  .  . 

Do 

Do 

3-toothed 

Do 

Do 

Greenish 

Low 

Do 

The  most  anomalous  subspecies  is  parishi,  but  except  for  a  single  character  this  form 
and  typica  are  very  much  alike.  The  two  are  practically  identical  in  habit,  odor,  and 
other  general  features.  Subspecies  parishi  is  not  "mainly  herbaceous"  as  Gray  was 
led  into  supposing  from  the  nature  of  the  types,  which  were  only  the  hurriedly  gathered 
tops  of  the  plants.  The  chief  distinguishing  mark  is  the  villous  or  almost  arachnoid 
pubescence  of  the  achenes.  This  often  is  accentuated  in  a  misleading  manner  through 
the  viscid  nature  of  the  surface  glands,  which  catch  and  hold  the  loose  tomentum  of 
the  involucre  during  the  process  of  dissection,  so  that  the  achenes  appear  more  copiously 
pubescent  than  they  really  are.  The  leaves  are  much  narrower  than  in  typical  trideiitata 
and  there  is  a  much  larger  percentage  of  entire  ones.  In  these  respects  parishi  is  quite 
similar  to  the  extremely  narrow-leaved  form  of  tridentata  once  named  by  Gray  as  variety 
angustifolia.  The  panicles  are  often  profuse,  with  widely  spreading  and  recurving  or 
even  pendant  branches.  Some  of  the  specimens  of  the  type  collection  exhibit  this  tend- 
ency to  a  limited  extent,  while  others  have  erect  branches.  Plants  with  drooping 
inflorescence  mingle  with  those  in  which  the  panicles  are  narrow  and  strictly  erect,  the 
other  characters  remaining  unchanged  (for  example,  Piru  Creek,  October  20,  1919, 
Hall).  This  feature  is  not  of  specific  value,  as  is  indicated  by  the  fact  that  a  parallel 
variation  occurs  in  A.  tridentata  typica.  In  specimens  otherwise  exact  typica,  the  drooping 
of  the  panicle  branches  is  sometimes  very  evident  (Carroll  Creek,  Sierra  Nevada  Moun- 
tains, California,  Museum  of  Vertebrate  Zoology;  Nighthawk,  Washington,  October  4, 
1911,  Jones).  Along  sandy  banks  of  irrigation  canals  and  other  streams  in  northwestern 
New  Mexico  the  plants  of  typica  often  display  beautifully  pendant  sprays  of  flowers 
(Hall  11124  UC),  and  in  alkaline  soil  of  northern  Nevada  dwarf  plants  have  been  found 
to  exhibit  the  same  feature,  perhaps  as  a  result  of  frequent  browsing  {Hall  11235,  UC). 
All  of  the  specimens  of  parishi  thus  far  collected  in  Antelope  Valley,  California,  have 
much  condensed  and  irregular  inflorescences,  this  perhaps  indicating  a  difi'erent  strain 


144 


GENUS   ARTEMISIA. 


from  those  growing  on  the  coastal  slopes,  or  this  may  be  only  the  result  of  unfavorable 
conditions  obtaining  in  that  bleak,  wind-swept,  and  more  elevated  valley.  The  most 
congested  inflorescences  are  on  plants  collected  in  1919,  after  three  years  of  exceptionally 
low  rainfall  (Hall  10959,  UC).  In  the  same  year  the  plants  on  the  coastal  slopes  had 
well-developed  inflorescences.  A  parallel  reduction  in  the  inflorescences  of  typica  is 
also  common  (for  example.  Granger,  Wyoming,  September  12,  1919,  Hall,  UC).  From 
these  various  considerations  it  is  seen  that  parishi  bears  all  the  evidence  of  being  a  local 
mutation  from  the  common  form  of  A.  tridentata. 

The  remaining  forms  of  A.  tridentata  are  all  of  small  size.  It  is  apparent  that  grazing 
and  burning  have  reacted  upon  the  sagebrush  itself  to  produce  a  series  of  new  dwarf 
forms  in  various  stages  of  fixation.  It  appears  certain  that  these  forms  have  arisen  in 
more  than  one  region,  and  hence  constitute  examples  of  polygenetic  origin.     Similar 


Fio.  21. 
UnuBual  leaves  of  Artemisia  tridentata  typica,  all 
from  sterile  shoots  of  a  single  plant  otherwise  typ- 
ical. Leevining  Grade,  Mono  County,  California, 
2,600  m.  altitude,  September  15,  1921,  ClemenU 
(UC).     AU  X  0.8. 


forms  have  been  produced  where  the  sagebrush  entered  rocky,  sterile,  or  subalpine  areas, 
as  in  the  case  of  trifida,  arbuscula,  nova,  and  rothrocki.  The  distribution  of  these  forms 
is  likewise  such  as  to  furnish  further  evidence  of  the  action  of  polygenesis.  This  is 
particularly  true  of  rothrocki,  which  occurs  only  in  Sierran  and  Rocky  Mountain  stations 
750  miles  apart. 

Of  all  these  dwarfed  subspecies,  nova  is  perhaps  the  one  which  most  closely  approaches 
typica.  Its  narrow  inflorescence  is  very  striking  in  the  extreme  form  and  is  commonly 
associated  with  low  stature.  This  combination,  to  which  is  to  be  added  the  small  number 
of  flowers  developed  in  each  head,  suggests  that  the  normal  nutrition  of  the  plant  may  be 
interfered  with.  This  subspecies,  whether  fixed  in  its  characters  or  not,  seems  to  be  the 
result  of  malnutrition,  as  is  indicated  by  the  fact  that  it  usually  and  perhaps  always 
grows  where  the  soil  is  shallow,  stony,  or  otherwise  unfavorable  to  full  development. 
Between  Strevell  and  Albion,  in  extreme  southern  Idaho,  the  plants  of  nova  are  not 
only  low  and  with  narrow  inflorescences,  but  they  are  also  quite  black  as  contrasted  with 
typica.  It  here  alternates  and  mixes  with  typica  on  apparently  uniform  soil  and  does 
not  intergrade  with  it.  This  suggests  that  it  may  be  a  more  palatable  strain  kept  low 
by  grazing.  In  other  places  the  subspecies  typica  itself  becomes  much  dwarfed,  espe- 
cially when  competing  with  grasses,  but  without  assuming  the  slender  habit  and  narrow 
inflorescence  of  nova.  At  other  times  it  takes  on  all  of  the  characters  of  nova,  except 
that  the  involucres  remain  canescent  (see  minor  variation  11).  This  nicely  indicates 
the  lack  of  unison  in  the  variation  of  the  characters  used  to  separate  the  two  forms. 
The  connection  between  typica  and  nova  may  be  indicated  by  citing  a  series  of  specimens 
with  the  former  at  one  end,  and  the  latter  at  the  other,  but  with  each  of  the  series 
differing  from  its  neighbor  by  only  a  single  trivial  character.    This  series,  easily  duplicated 


A.   TRIDENTATA, 


145 


in  any  large  herbarium,  has  been  constructed  from  specimens  in  the  herbarium  of  the 
University  of  California  as  follows: 

(1)  Typica,  near  Empire,  Colorado,  Patterson  219  (UC  29790). 

(2)  Reduced  size  without  other  change,  west  of  Hosier,  Wyoming,  September  10,  1919,  Clements  (UC).     Minor 

variation  15. 

(3)  Same  as  2,  but  with  reduced  upper  leaves,  south  of  Laramie,  Wyoming,  September  9,  1919,  Hall  (UC). 

(4)  Same  as  2,  but  with   narrow  inflorescence.  Mono  County,  California,  August   18,   1898,  Congdon   (UC). 

Minor  variation  11. 

(5)  Same  as  4,  but  with  green  involucres,  Laramie,  Wyoming,  Nelson  S1S5  (UC,  146504).     Genuine  nova. 

In  the  subspecies  trifida  the  narrow  inflorescence  is  combined  with  a  foliage  more 
deeply  cleft  than  in  either  typica  or  nova.  This  tendency  toward  cleft  or  parted  leaves 
is  common  also  in  other  subspecies,  that  is,  it  combines  promiscuously  with  other  char- 
acters. It  is  especially  frequent  in  arbuscula  {Heller  12914,  from  Placer  County,  Cali- 
fornia, etc.),  highly  developed  in  some  specimens  of  spiciformis  {Nelson  8941a,  from 
Albany  County,  Wyoming,  etc.),  and  a  form  of  the  latter  has  been  named  A.  spiciformis 
longiloba   (Osterhout,   Muhlenbergia  4:69,   1908).     Although  the  character  has  been 


FiQ.  22. 
Artemisia  tridentata  trifida,  A.  t.  bolanderi, 
and  A.  carta:  a,  b,  c,  all  from  the  aame  plant,  re- 
ferred to  trifida  but  perhaps  a  hybrid  between  this 
and  cana  (Lima,  Montana,  Hall  11569);  d,  from 
A.  t.  bolanderi  (Mono  County,  California,  Clements 
and  Hall  11702);  e,  an  unusual  form  of  cana  from 
Wyoming  (Hall  10992),  listed  as  minor 
All  X  1. 


accepted  as  of  specific  value  in  the  case  of  trifida,  it  is  usually  passed  over  as  a  trivial 
variation  when  it  occurs  in  these.  In  the  present  paper  it  is  used  as  a  character  to  aid 
in  the  recognition  of  a  variety  of  long  standing  in  the  literature,  marked  also  by  its  narrow 
inflorescence  and  an  indescribable  thyme-like  aspect  of  the  leafy  twigs.  It  should  be 
emphasized,  however,  that  not  all  of  the  sagebrushes  with  trifid  leaves  belong  to  the 
subspecies  trifida. 

The  next  two  subspecies,  that  is,  arbuscula  and  rothrocki,  differ  from  the  four  already 
discussed  in  having  usually  larger  heads.  The  difference  is  not  so  great,  however,  as 
the  measurements  given  in  descriptions  would  seem  to  indicate,  for  specimens  are  fre- 
quently found  which,  although  plainly  of  this  group,  have  heads  scarcely  larger  than  in 
the  other  subspecies.  The  size  of  the  involucre  is  associated  with  the  number  of  flowers 
which  it  incloses,  and  this  is  evidently  a  more  definite  criterion  for  general  use.  From 
table  14  it  will  be  seen  that  the  number  of  flowers  in  the  subspecies  thus  far  discussed 
is  3  to  6,  rarely  7,  8,  or  9,  while  in  these  two  the  number  runs  from  6  to  13  and  even  to  20 
in  erratic  plants,  and  is  only  rarely  as  low  as  4  or  5.  While  there  is  thus  a  notable  tend- 
ency in  opposite  directions,  the  overlapping  is  sufficient  to  indicate  that  the  two  groups 
of  subspecies  are  not  specifically  distinct. 

The  subspecies  arbuscula  is  apparently  more  primitive  than  rothrocki,  or  at  least  it 
presents  less  evidence  of  being  a  highly  modified  form.  It  is  a  low,  straggling  shrub  with 
numerous  rigid  branches  and  is  especially  suited  to  the  rigorous  environment  in  which  it 
grows.  Its  popular  name  of  scabland  sagebrush  is  indicative  of  the  unfavorable  soil  and 
moisture  conditions  with  which  it  must  contend.  It  seems  almost  certain  that  it  is  a 
derivative  of  typica  developed  under  the  unfavorable  conditions  so  common  to  the 


146 


GENUS   ARTEMISIA. 


northerly  part  of  the  area  covered  by  A.  tridentata.  In  his  original  description  Nuttall 
included  with  this  some  specimens  of  what  is  now  known  as  nova,  another  subspecies 
also  adapted  to  a  severe  environment  but  along  somewhat  different  lines. 

The  subspecies  rothrocki  is  of  uncertain  derivation.  Its  sporadic  occurrence  at  widely 
separated  localities  indicates  that  it  is  of  polygenetic  origin.  In  this  case  the  parent 
quite  certainly  is  typica,  since  none  of  the  other  forms  has  a  range  sufficiently  extensive 
to  cover  all  of  the  stations  for  rothrocki.  The  attempt  of  others  to  specifically  recognize 
forms  here  included  under  this  subspecies  would  seem  to  indicate  that  it  is  not  homo- 
geneous, but  when  identical  forms  are  found  in  areas  so  widely  separated  as  California 
and  Colorado  the  distinctions  break  down  entirely.  The  proposals  referred  to  are 
spiciformis  and  vaseyana,  both  of  which  are  fully  discussed  under  the  heading  of  minor 
variations.  The  identical  forms  are  perhaps  best  considered  as  parallel  variations  from 
the  parent  typica  stock.    The  large  number  of  flowers  in  the  head  may  indicate  rothrocki 


Table  14. — Variation  in  the  subspecies  of  Artemisia  tridentata. 


No.  of 
flowers 
per  head. 


Length  of 
corolla. 


Subspecies  lypica: 

Medicine  Bow,  Wyo .  . . 

Hosier,  Wyo.' 

West  of  Bosler,  Wyo> .  . 

Do.' 

Clear  Creek,  Colo 

Tintic,  Utah 

Snowville,  Utah 

Albion,  Idaho 

Eastern  Oregon 

Weber  Canon,  Utah.  .  . 
Pleasant  Valley,  Greg.  . 
Siskiyou  County,  Calif. 
Shasta  Valley,  Calif.... 

Mint  Cafion,  Calif 

Kern  County,  Calif.  .  .  . 
Nighthawk,  Wash 


Average. 


Subspecies  pariehi: 

Rosamond,  CaUf 

Do 

Do 

Newhall,  Calif.' 

Ventura  County,  Calif. 
Mojave  Desert,  Calif. . . 
Carson  Sink,  Nev 


Average . 


Subspecies  nova: 

South  of  Laramie,  Wyo 

Albany  County,  Wyo 

Laramie,  Wyo 

Laramie  Hills,  Wyo 

San  Francisco  Mountains,  Ariz. 

Buckskin  Mountains,  Ariz 

Panguitch  Lake,  Utah 

Mount  Irish,  Nev 

Strevell-Albion,  Idaho 

Inyo  Range,  Calif 


Average . 


CI 
CI 
CI 
CI 
29790  UC 

172630  UC 
CI 
CI 
29789  UC 
CI 
CI 

166157  UC 

CI 

CI 

34171  UC 

176960  UC 


CI 

75851  UC 
74055  UC 
54010  UC 

205802  UC 
Gr 

128181  UC 


CI 
69457  UC 
146504  UC 
91181  UC 
135368  UC 
159117  UC 
159393  UC 
135367  UC 
CI 
202351  UC 


mm. 
3.0 
3.0 
3.2 


2.1 
2.7 
2.5 
2.1 


9  11 
13  14 
10  14 


10  11 
9 
16  17 


4  4 

4  4 

4  5 

4  4 

4  5 

4  5 

3  3 

4  4 

3  4  5 

4  5 

3  4 

4  4 

3  4 

4  6  5 


13  11 
16  19 

9  11 
12  13 

9  10 


13 


8  10 
6     7 

8  7 

9  9 


2.0 
2.2 
2.7 
2.5 
2.0 
2.4 
2.4 
2.4 
2.5 
2.0 
2.0 
Young 
2.5 
2.6 
2.0 
2.0 


2.2 


2  0 
2  3 
young 
2.4 
2  6 
2.0 
2.0 


2.3 


2.1 

2.6 

3.0 

2.4 
Young 

2.5 

2.5 
Young 

1.9 
Young 

2.4 


A.    TRIDENTATA. 
Table  14. — Variation  in  the  svbspeeies  of  Artemisia  tridentata — Continued. 


147 


No.  of 
flowers 
per  head. 


Subspecies  trifida: 

South  of  Laramie,  Wyo 

Do 

Do 

Teton  Forest,  Wyo 

Yellowstone,  Wyo 

Near  Strevell,  Idaho 

Madison.  Mont 

Cascade  Mountains,  Wash 

Oroville,  Wash 

Rattlesnake  Mountains,  Wash. 
Eastern  Oregon 


Average . 


Subspecies  arhuscula: 

Yakima  Region,  Wash 

Crook  County.  Oreg 

Lake  County,  Oreg 

Eastern  Oregon 

Silver  Lake,  Oreg 

Placer  County,  Calif.' 

Hayden  Flats,  Routt  County,  Colo . 
Eldorado  County,  Calif 


Average . 


Subspecies  rothrocki: 

Mount  Olancha,  Calif 

Tioga  Pass,  Calif 

San  Bernardino  Mountains, 

Inyo  County,  Calif 

Mount  Dana,  Calif 

Do 

California 

Middle  California 

Mariposa  County,  Calif.  . . 

Camas  Prairie,  Idaho 

Red  Cliff,  Colo* 

North  Park,  Colo.< 

Slide  Mountain,  Nev 

Washington' 

Union  County,  Oreg 

Type  specimen 

Cooper  Hill,  Wyo 

Crested  Butte,  Colo.« 

Yakima  Region,  Wash.  .  . . 
Wallowa  Mountains,  Oreg. 

Placer  County,  Calif 

Truckee,  Calif 


Average . 


CI 
CI 
CI 

NY 

NY 

CI 

NY 

172638  UC 

175975  UC 

NY 

29793  UC 


172649  UC 

176735  UC 
175219  UC 

176736  UC 
176784  UC 
202223  UC 

NY 
205842  UC 


47383  US 

203183  UC 

101098  UC 

202294  UC 

29666  UC 

29806  UC 

34702  UC 

91185  UC 

29710  UC 

231676  US 

NY 

NY 

NY 

NY 

NY 

Phila. 

146493  UC 

34512  UC 

173161  UC 

29788  UC 

193453  UC 

193454  UC 


4.0 
4.1 
4.1 
4.1 
4.0 
4.0 


4.0 
4.2 
3.5 
4.2 
4.1 
5.0 
4.0 
5.0 
4.6 
4.5 
3.2 
3.5 
2.7 
3.0 
2.8 
4.0 
3.3 
3,7 
3.0 
3.0 
3.2 
2.7 


11  13 
8  12 
16  14 


8  10 
10  10 
10  10 

8  8 
10  12 
10  12 


11 


12 

11  13 

12  14 
14  14 

10  12 

11  14 

12  12 
12   13 

13 


9  10 
11     8 

7  10 
13  12 
13  14 
13  16 

9  10 

7  8 
2  13 

8  11 


8  10 
10  10 
18  20 

12  13 

13  13 

9  10 
9  10 


2.3 
2.0 
2.3 
2.4 
2.5 
2.3 
2.0 
2.0 
2.2 
Young 


2.6 
2.8 
Young 
2.4 
3.0 
3.3 


2.4 
2.7 
3.0 
2.9 
2.9 
2.8 
2.5 
2.8 
2.8 
2.8 


'  Dwarf  forms. 

'  Type  collection  of  A.  parishi  Gray. 

•  Minor  variation  10. 


'  Minor  variation  7,  A.  spidformia  Osterhout. 

'  Type  of  A.  taaeyana  Rydberg,  minor  variation  18. 


as  the  most  primitive  of  all  the  subspecies,  but  it  is  not  the  beginning  of  A.  tridentata, 
as  seems  evident  from  its  lack  of  connection,  either  morphologically  or  geographically, 
with  A.  bi^eZow,  which, as  previously  shown  (pp.  104, 142), seems  to  represent  the  ancestral 
type  from  which  this  collective  species  has  sprung.  Whatever  its  previous  history, 
rothrocki  is  now  a  readily  distinguished  type,  restricted  in  distribution  to  a  few  widely 
separated  localities,  all  within  the  general  area  of  typica,  but  near  its  uppermost  limits 


148  GENUS   ARTEMISIA. 

in  the  mountains.  While  apparently  always  at  high  altitudes,  it  commonly  occupies  the 
belt  between  the  grassland  and  the  higher,  better  drained,  but  less  fertile  slopes  where 
typica  abounds. 

The  least  known  of  all  the  subspecies  is  bolanderi.  This  was  based  upon  specimens 
said  to  be  gathered  at  Mono  Pass,  California,  but  perhaps  they  came  from  well  down 
the  eastern  side  of  the  Sierra  Nevada.  It  is  most  like  trifida  in  shape  and  lobing  of  the 
leaves,  but  has  larger  heads  with  more  flowers  and  the  white  tomentum  is  loose,  not 
closely  appressed  as  in  that.  The  type  collection  consists  only  of  flowering  twigs  and 
the  leaves  are  nearly  all  entire.  The  only  other  collection  is  one  from  2,400  meters 
altitude  at  Sand  Flat,  south  of  Mono  Lake,  California  {Clements  and  Hall  11702).  In 
this  the  leaves  are  largely  trifid,  and  it  therefore  seems  likely  that  the  lower  ones  of'the 
type  were  also  more  generally  cleft  than  in  the  portions  preserved.  The  Sand  Flat 
plants  were  growing  in  the  main  belt  of  typical  tridentata,  but  on  an  exceptionally  cold 
and  bleak  plain  where  they  were  competing  with  a  low,  turf-forming  Sporobolus.  It  is 
conceivable  that  these  conditions  are  responsible  for  the  modification  of  tridentata  into 
this  form  and  that  trifida  was  similarly  produced  along  the  northern  limits  of  the  range 
of  the  species.  A  nearly  identical  form  has  been  noted  as  minor  variation  4  of  ^.  cana. 
Except  for  the  preponderance  of  entire  leaves,  which  are  also  somewhat  longer,  this 
duplicates  bolanderi  and  indicates  the  possibility  of  the  origin  of  morphologically  equiva- 
lent plants  from  quite  different,  although  related,  stocks.  Figure  22  shows  the  manner 
in  which  leaves  of  trifida  and  bolanderi  sometimes  come  to  look  much  alike  (except 
in  the  loose,  white  pubescence  of  the  latter)  and  also  the  similarity  of  both  to  occasional 
leaves  of  the  variation  from  A.  cana  just  mentioned. 

A  recent  suggestion  by  Smiley  (Univ.  Calif.  Publ.  Bot.  9:396,  1921)  that  bolanderi 
may  be  a  hybrid  between  typical  tridentata  and  rothrocki  will  be  further  investigated  in 
the  field.  It  is  not  believed,  however,  that  the  latter  grows  in  the  neighborhood  of  the 
Sand  Flat  station  cited  above. 

A  study  has  been  made  of  variation  in  the  shape  of  the  inner  bracts  of  the  involucre 
in  subspecies  bolanderi,  since  in  the  original  description  Gray  described  these  as  "nar- 
rowly oblong"  as  contrasted  with  the  "broad"  bracts  of  A.  cana,  and  this  difference 
has  been  used  by  later  writers  as  a  specific  criterion.  However,  when  dissected  out 
and  carefully  compared,  it  is  found  that  the  inner  bracts  of  heads  from  the  type  col- 
lection, although  smaller,  are  not  essentially  different  in  shape  from  those  commonly 
found  in  A.  cana  (see  fig.  23). 

ECOLOGY. 

Artemisia  tridentata  is  typically  a  low  shrub,  but  it  ranges  from  a  dwarf  form  less 
than  a  foot  high  to  a  small  tree  20  feet  high.  It  is  the  characteristic  dominant  of  the 
sagebrush  climax  of  the  Great  Basin,  where  it  often  forms  a  pure  consociation  over  large 
areas.  It  ranges  far  beyond  the  climax  area  into  the  mixed  prairie  and  bunch-grass 
prairie,  especially  where  overgrazing  has  given  it  the  advantage  in  competition  with  the 
grasses.  This  is  especially  true  of  the  bunch-grass  association  in  eastern  Oregon,  north- 
eastern California,  and  southern  Idaho,  which  has  been  almost  completely  replaced  by 
sagebrush.  The  latter  seems  to  have  all  the  marks  of  a  climax  community,  but  the 
abundance  of  the  bunch-grass  dominants  in  protected  places  makes  it  clear  that  the 
sagebrush  has  become  controlling  only  in  the  historical  period  as  a  result  of  overgrazing. 
On  the  east  the  sagebrush  makes  a  broad  mictium  with  the  mixed  prairie  in  Wyoming, 
in  which  it  is  favored  by  the  overgrazing  of  the  more  palatable  grasses.  In  the  western 
edge  of  the  Dakotas  and  Nebraska  it  becomes  a  subclimax  community  of  the  more 
stable  valleys  of  the  Bad  Lands.  The  sagebrush  scarcely  reaches  the  plains  of  Colo- 
rado, owing  to  the  mountain  barriers,  but  it  is  more  or  less  abundant  in  the  mixed 


A.    TRIDENTATA.  149 

prairie  of  several  of  the  great  parks.     The  mictium  of  sagebrush  and  mixed  prairie  is 
a  characteristic  feature  of  northwestern  New  Mexico  and  northeastern  Arizona. 

While  the  greatest  contact  of  sagebrush  is  with  the  bunch-grass  and  mixed  prairies, 
it  touches  the  desert  scrub  in  Nevada  and  in  a  few  places  in  desert  California.  It  makes 
occasional  contacts  with  the  coastal  sagebrush  in  southern  California  and  northern 
Mexico,  but  usually  as  more  or  less  isolated  communities.  It  frequently  constitutes 
parks  with  the  pinon-cedar  woodland  from  Nevada  to  New  Mexico,  and  these  are 
usually  connected  by  a  kind  of  sagebrush-cedar  savannah.  It  sometimes  bears  a  similar 
relation  to  the  lower  portion  of  the  yellow-pine  woodland,  and  on  the  west  slope  of  the 
Rocky  Mountains  is  often  mixed  with  Petran  chaparral. 


Fia.  23. — Inner  bracts  of  the  involucre  of  Artemisia  tridentata  holandtri  and  A.  cana:  a,  b,  e,  from  the  type  collection 
of  bolanderi  (29805  UC);  d,  e,  froaa  typioil  cana  (70518  UC);  /,  g,  also  from  typical  cana  (51692  UC).     All  X  8. 

The  most  frequent  associates  of  A.  tridentata  are  the  other  shrub  dominants  of  the 
sagebrush  association.  Chief  among  these  is  Atriplex  confertifolia,  followed  closely  by 
Chrysothamnus  nauseosus  and  viscidiflorus.  Other  important  associates  are  Atriplex 
canescens,  Grayia  spinosa,  Tetradymia  spinosa,  and  Eurotia  lanata.  Among  the  dwarf 
shrubs  the  most  important  are  Gutierrezia  sarothrae  and  Kochia  vestita,  the  former  indi- 
cating disturbance  in  some  degree  and  the  latter  the  presence  of  alkali.  The  sagebrush 
proper  is  also  frequently  associated  with  one  or  more  of  its  variads,  such  as  A.  <.  arbus- 
cula,  nova,  and  trifida,  as  well  as  with  other  species  of  Artemisia,  such  as  cana,  rigida, 
and  spinescens.  In  practically  all  these  cases,  the  different  forms  alternate  rather  than 
mix  intimately,  corresponding  to  some  factor  difference,  usually  of  water.  For  example, 
A.  cana  is  usually  found  below  tridentata  in  valley  or  depressions,  while  the  latter  oc- 
cupies small  valleys  and  ravines  below  trifida. 

The  typical  form  of  the  sagebrush  is  an  indicator  of  deep  soils  of  somewhat  greater 
water-content  and  largely  free  from  alkali.  While  it  occurs  frequently  with  such  halo- 
phytes  as  Kochia  and  Sarcobatus,  it  either  alternates  with  them  or  its  working  roots 
probably  occupy  a  less  saline  layer  of  the  soil.  It  is  found  also  on  rocky  slopes  and 
ridges,  but  usually  in  the  deeper  pockets  of  soil,  and  as  a  result  of  the  higher  water- 
content  due  to  the  lack  of  competition.  In  the  mixed  prairie  and  especially  in  the 
Bad  Lands,  it  is  an  indicator  of  greater  water-content.  While  the  sagebrush  does  form 
root-sprouts  to  some  extent,  this  is  not  sufficient  to  make  it  an  indicator  of  fire  as  a 
rule,  except  when  a  dwarf  form  is  produced. 

Of  the  subspecies  of  tridentata,  one,  parishi,  resembles  it  in  practically  all  ecological 
respects,  while  the  others,  arbuscula,  bolanderi,  nova,  rothrocki,  and  trifida,  are  char- 
acteristically dwarfed,  as  is  true  also  of  the  typical  form  in  less  favorable  conditions. 
They  occupy  the  thinner  or  drier  soils,  with  the  exception  of  rothrocki,  which  prefers 
meadows  and  depressions  in  the  subalpine  region,  while  typica  occupies  the  drier  slopes. 
Two  dwarf  forms  of  the  latter,  one  of  recent  and  the  other  of  more  remote  origin,  are 
typical  indicators  of  fire  and  overgrazing,  to  which  they  doubtless  owe  their  origin. 


150  GENUS   ARTEMISIA. 

USES. 

The  common  sagebrush  or  "black  sage,"  as  it  is  often  erroneously  called,  is  by  far  the 
most  important  species  of  Artemisia  in  western  North  America  as  regards  its  value  as  a 
browse  shrub.  This  is  largely  because  of  its  abundance  over  large  areas  and  its  ability 
to  withstand  close  cropping,  even  by  sheep.  It  is  of  special  value  in  the  autumn  and 
winter  when  grass  and  other  pasturage  is  dried  up  or  covered  with  snow.  At  other 
seasons  it  is  much  less  browsed  by  free-ranging  animals.  The  testimony  of  range  experts 
varies  as  to  its  exact  value  for  different  kinds  of  stock.  This  is  because  of  the  greater 
need  in  some  places  of  browse  shrubs,  even  less  palatable  ones  like  this,  and  also  because 
certain  breeds  of  animals  are  more  fastidious  than  others  of  the  same  species.  Hence, 
reports  range  from  "eaten  by  sheep  but  not  by  starving  cattle"  to  "good  browse  for 
cattle  and  sheep"  and  "excellent."  Direct  observation  by  the  authors  shows  that  sage- 
brush is  not  much  eaten  by  horses,  but  that  it  enables  stockmen  to  carry  enormous  num- 
bers of  cattle  through  the  winter  months,  and  that  it  is  the  principal  dependence  of 
sheep  in  many  districts  during  periods  of  drought  and  in  the  winter.  A  chemical  analysis 
of  the  plant  is  given  by  Dinsmore  and  Kennedy  (Nevada  Exp.  Sta.  Bull.  62:38,  1906). 
The  close  cropping  by  animals  markedly  affects  the  branching,  size,  and  general  appear- 
ance of  the  shrubs.  Sometimes  this  results  in  all  of  the  plants  being  much  dwarfed  and 
it  is  now  infrequent  to  find  the  large,  normally  formed,  tree-like  growths  that  must  have 
been  the  usual  type  before  stock  was  introduced. 

The  Indians,  and  also  many  of  the  white  settlers,  find  much  use  for  sagebrush  in  the 
construction  of  shelters  and  for  fuel.  The  stems  are  usually  too  irregular  and  brittle  to 
serve  well  for  construction,  although  sometimes  so  used,  but  the  branches  are  employed 
as  thatch  in  the  building  of  temporary  houses  and  sheds.  The  wood  makes  a  quick,  hot 
fire,  partly  because  of  the  oil  and  partly  because  of  the  dry  shredded  bark. 

This  shrub  has  been  cultivated  as  an  ornamental  since  1881,  but  apparently  it  has  not 
found  much  favor.  It  is  especially  suited  to  dry  or  stony  situations,  and  its  value  lies 
chiefly  in  the  clean  gray  foliage.  The  larger  forms,  with  expanded  drooping  inflores- 
cences, such  as  mentioned  under  minor  variation  14,  would  be  the  most  desirable  for  this 
purpose. 

Attempts  have  been  made  in  the  West  to  utilize  sagebrush  for  its  rather  high  content 
of  potash,  but  the  cost  of  preparation  was  found  to  be  prohibitive.  It  has  also  been  used 
to  a  limited  extent  for  a  flotation  oil  in  mining  and  smelting  operations,  but  again  its  cost 
was  found  to  be  greater  than  that  of  other  oils  equally  useful.  Less  complex  substances 
are  now  more  in  demand  for  this  purpose.  The  report  that  sagebrush  contains  rubber  is 
entirely  erroneous. 

A  common  malady  in  the  West,  known  as  mountain  fever,  but  in  reality  only  a  form 
of  hay-fever,  has  been  demonstrated  to  be  due  in  many  cases  to  the  pollen  of  Artemisia 
tridentata.  This  pollen  is  produced  in  great  abundance  and  is  so  light  that  it  is  easily 
carried  in  enormous  quantities  by  the  wind.  Its  saline  extract  is  now  used  as  a  preven- 
tive for  hay-fever  after  the  manner  described  under  A.  vulgaris  (p.  100). 

26.  ARTEMISIA  CANA  Pursh,  Fl.  Am.  Sept.  521,  1814.  Plate  21.  Hoary  Sagebrush. 
A  low  shrub,  commonly  4  to  9  but  sometimes  15  dm.  high,  with  pungent  turpentine- 
like odor;  stems  freely  branched  throughout,  forming  rounded  bushes,  the  older  parts 
with  a  dark-brown  fibrous  bark,  the  branches  densely  clothed  with  a  gray  or  yellowish- 
green  tomentum  which  masks  the  striae;  principal  leaves  sessile,  linear,  acute,  2  to  4  or 
5  cm.  long,  1  to  4  mm.  wide,  entire  or  occasionally  with  1  or  2  irregular  teeth  or  lobes, 
silky-canescent  or  floccose  or  sometimes  glabrate  and  slightly  viscid  in  age;  upper  leaves 
scarcely  different  and  only  sUghtly  reduced  even  to  midway  of  the  inflorescence,  silky- 
pubescent;  inflorescence  a  narrow  leafy  panicle,  15  to  30  cm.  long,  2  to  6  cm.  broad; 


A.    CANA.  151 

heads  homogamous,  mostly  sessile  in  small  glomemles,  erect;  involucre  campanulate,  4 
to  5  mm.  high,  3  to  4  mm.  broad,  or  considerably  smaller  in  minor  variation  4  in  which 
the  heads  are  crowded  and  small;  bracts  8  to  15,  the  outer  orbicular  or  abruptly  narrowed 
above,  the  inner  elliptic-spatulate,  very  obtuse,  broadly  scarious-margined,  canescent 
or  tomentose;  ray-flowers  wanting;  disk-flowers  6  to  15  or  rarely  20,  fertile,  corolla  tubu- 
lar-funnelform,  sharply  5-toothed,  2  to  3  mm.  long,  resinous-glandular;  style-branches 
disk-like  at  summit,  the  margins  lacerate;  achenes  cylindric-turbinate,  truncate  and  with 
a  slightly  raised  rim  at  summit,  angled  or  with  4  or  5  evident  ribs,  granuliferous. 

On  the  plains  and  lower  mountains,  Saskatchewan  to  western  Nebraska,  New  Mexico, 
Utah,  northeastern  California,  British  Columbia,  and  Alberta.  Type  locality,  on  the 
Missouri  River.  Collections:  Saskatchewan  Plains,  Macoun  1011  (Gr);  Indian  Head, 
Assiniboia,  September  3,  1891,  Spreadbough  (US);  Bozeman,  Montana,  September  3, 
1902,  W.  W.  Jones  (DS,  Gr,  UC,  US) ;  Fort  Bedford,  North  Dakota,  Waldron  4I8  (NY) : 
Centennial,  southeastern  Wyoming,  Goodding  2118  (Gr,  NY,  UC,  US);  Sioux  County, 
Nebraska,  June  17,  1897,  Bates  (Gr);  Steamboat  Springs,  Routt  County,  Colorado, 
Osterhout  2012  (Osterhout,  NY,  UC,  type  collection  of  A.  cana  viscidula  Osterhout,  minor 
variation  1);  Marshall  Pass,  Colorado,  Baker  880  (Gr,  NY,  UC,  US);  Fish  Lake,  Utah, 
Jones  5824  (NY,  UC) ;  Dulce,  Rio  Arriba  County,  New  Mexico,  Bailey  908  (US) ;  30  km. 
north  of  Bridgeport,  Mono  County,  California,  Hall  11690  (UC);  Little  Truckee  River, 
California,  September  1887,  Sonne  (UC);  near  Reno,  Nevada,  Kennedy  374-  (UC);  Lake 
County,  Oregon,  Cusick  2737  in  part  (Gr,  NY,  UC,  US) ;  Caribou  Forest,  Idaho,  Eggles- 
ton  9975  (US). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Artemisia  cana  viscidula  Osterhout,  Bull.  Torr.  Club  27:507,  1900. — A  state  or  condition  of  A.  cana 
in  which  the  tomentum  is  light  and  obscured  by  a  glutinous  exudate,  the  herbage  therefore  greenish.  Type 
locality,  Steamboat  Springs,  Routt  County,  Colorado. 

2.  A.  coLUMBiENSis  Nuttall,  Genera  2:142,  1818. — A.  cana.  In  connection  with  the  original  description 
Nuttall  states  that  this  "appears  to  be  A.  cana  of  Pursh,"  but  later  on  he  says  that  it  is  "certainly  distinct 
from  the  A.  cana  of  Pursh"  (Trans.  Am.  Phil.  Soc,  II,  7:399,  1841).  No  differentiating  characters  are  given 
other  than  that  the  leaves  are  all  entire.  A  specimen  in  the  herbarium  of  the  Philadelphia  Academy  of  Sciences 
labeled  as  from  the  banks  of  the  Missouri  and  Columbia  Rivers  and  indicated  by  Nuttall  as  one  of  the  types  is 
plainly  A.  cana. 

3.  A.  VISCIDULA  Rydberg,  Bull.  Torr.  Club  33:157,  1906. — Based  upon  A.  cana  viscidula  Osterhout,  which 
see.  Later  reduced  by  Rydberg  to  A .  cana  (N.  Am.  Fl.  34 :  282, 1916) ,  a  disposal  with  which  the  present  authors 
agree. 

4.  An  unnamed  form  with  linear  mostly  entire  leaves  only  about  1  mm.  wide,  on  short,  crowded  twigs  is 
occasionally  found  in  Wyoming:  Evanston,  Hcdl  10992;  40  km.  west  of  Rawlins,  Hall  10991;  west  of  Laramie, 
September  10,  1919,  Clements.  As  far  as  observed  these  always  grow  in  the  proximity  of  plants  of  typical  cana 
and  all  show  evident  injury  to  the  main  stems,  perhaps  by  browsing.  This  latter  is  believed  to  be  responsible 
for  some  of  the  changed  characters.  Except  for  the  entire  leaves,  these  plants  are  like  A.  tridentata  bolanderi, 
and  even  this  distinction  does  not  constantly  hold,  since  occasional  leaves  are  cleft,  as  shown  in  figure  22.  The 
twig  illustrated  is  exceptional,  since  most  of  the  leaves  on  this  plant  are  entire.  In  one  collection  (10991)  the 
involucral  bracts  are  almost  exactly  like  those  shown  of  bolanderi  (fig.  23,  a,  b,  c);  in  another  (10992)  the  bracts 
are  like  the  last  two  drawings  of  genuine  cana  (fig.  23,  /,  g),  but  of  smaller  size,  corresponding  to  the  reduced  size 
of  the  heads. 

RELATIONSHIPS. 

In  technical  characters  as  well  as  in  habit  this  species  finds  its  nearest  ally  in  A.  tri- 
dentata. Its  whiter  silvery  pubescence  and  longer  upper  leaves  serve  to  distinguish  it  in 
the  field.  These  leaves  are  typically  entire  and  acuminate  as  contrasted  with  the 
uniquely  3-toothed  leaves  on  all  but  the  upper  twigs  of  tridentata.  Moreover,  each  of 
the  subspecies  of  the  latter  has  some  individual  peculiarity  which  serves  to  distinguish  it. 
In  the  case  of  tridentata  typica,  the  one  most  likely  to  be  confused  with  cana,  this  consists 
in  a  reduced  number  of  flowers,  only  4  to  6  as  contrasted  with  6  to  20  in  cana.    The  close- 


152 


GENUS   ARTEMISIA. 


ness  of  relationship  is  indicated  by  an  occasional  lobe  on  some  of  the  leaves,  and  usually 
when  this  is  present  it  has  very  much  the  shape  and  direction  of  the  lobes  in  certain 
subspecies  of  tridentata  with  cleft  foliage.  It  is  also  significant  that  the  inflorescence, 
heads,  and  flowers  of  A.  tridentata  rothrocki  so  nearly  duplicate  those  of  certain  forms  of 
A.  cana  that  specimens  can  be  identified  with  certainty  only  when  lower  leaves  are  pres- 
ent. The  geographic  ranges  of  the  two  overlap  along  a  large  extent  of  territory,  from 
Utah  and  northern  California  nearly  to  the  Canadian  boundary,  and  they  sometimes 
bring  the  two  species  into  the  same  ecologic  habitat.  To  the  south  of  this  belt  inhabited 
by  the  two  in  common,  only  tridentata  is  found,  this  occurring  in  abundance  even  to 
beyond  the  Mexican  border,  while  to  the  north  cana  makes  its  way  well  up  into  Canada. 
Since  tridentata  is  of  southerly  origin,  as  has  been  already  demonstrated,  the  natural 
conclusion  from  a  consideration  of  these  facts  of  distribution  is  that  cana  is  a  derivative 
of  this  abundant  and  widespread  species. 

The  relationships  of  the  forms  here  included  under  A.  cana  have  been  sufficiently  dis- 
cussed in  deahng  with  the  minor  variations.  Table  15  supplies  the  evidence  upon  which 
some  of  the  conclusions  were  based. 


Table  15. — Variation  in  Artemisia  cana. 


Genuine  cana: 

Gallatin  County,  Mont 

Montana  (part) 

Do 

Centennial,  Wyo 

West  of  Laramie,  Wyo 

Seven  Mile  Lake,  Wyo 

Howell  Lake,  Wyo 

Fish  Lake,  Utah 

Little  Truckee  River,  Calif. 

Lake  County,  Oreg 

Near  Prineville,  Oreg 

Steamboat  Springs,  Wyo.' .  . 


Average. 


Minor  variations: 

West  of  Laramie,  Wyo.' 

Evanston,  Wyo.' 

West  of  Rawlins,  Wyo.» 
Teton  Forest,  Wyo 


Average. 


166429  UC 
29729  UC 
29729  UC 
70518  UC 
CI 
51692  UC 
51638  UC 
160265  UC 
193576  UC 
34375  UC 
176719  UC 
2012  Osterh 


CI 

205534  UC 

205535  UC 
177138  UC 


4.0 
4.5 
5.0 

5.0 
4.0 
5,2 
4.5 


.5  3.0 
.8  3.4 
.5     3.6 


2.3  2.5 

2.5  2.7 

2.2  2.4 

2.7  2.5 


2  5 


No.  of 
flowers 
per  head. 


Length 
of  disk- 
corolla. 


2.9 
2.5 
2.5 
2.5 
2.7 
2.7 


'  Type  of  variety  viscidula  Osterhout.     See  minor  variation 


'  Minor  variation  4 ;  heads  crowded  and  i 


ECOLOGY. 

Artemisia  cana  closely  resembles  A.  tridentata  in  habit,  as  well  as  in  the  tendency  to 
form  pure  communities.  It  requires  more  water  and  hence  often  constitutes  a  subclimax 
consocies  in  valleys  of  the  northern  half  of  the  sagebrush  formation.  In  Montana 
especially  it  replaces  the  sagebrush,  forming  valley  communities  subclimax  to  the  mixed 
prairie,  and  making  a  low  savannah  with  the  grasses  as  it  disappears  before  the  climax. 
In  the  Bad  Lands  of  Montana  and  North  Dakota  it  often  plays  an  important  role  in  the 
succession,  preceding  the  final  grasses.  It  is  regularly  an  indicator  of  greater  water- 
content,  though  in  bad-land  areas  this  is  the  result  of  a  lack  of  competition. 


A.    RIGIDA.  153 

USES. 

The  principal  use  of  this  sagebrush  is  as  a  browse  shrub,  especially  for  sheep.  Accord- 
ing to  experts  in  grazing  it  is  very  important  throughout  most  of  its  range  and  is  eaten 
quite  extensively  when  other  feed  is  scarce.  In  eastern  California,  where  commonly 
known  as  "white  sagebrush,"  it  is  reported  as  a  good  browse  shrub,  even  for  horses  and 
cattle. 

Together  with  A.  tridentata,  it  furnishes  settlers  and  campers  with  fuel  and  shelter 
and  is  much  used  for  these  purposes  by  the  Indians,  especially  in  regions  where  trees  are 
scarce.  In  England,  it  is  cultivated  to  a  limited  extent  as  an  ornamental,  because  of  its 
silvery  leaves  and  stems.  Finally,  its  importance  both  as  a  cause  and  a  remedy  for  hay- 
fever  is  perhaps  no  less  than  that  of  A.  tridentata  in  proportion  to  its  relative  abundance. 

27.  ARTEMISIA  RIGIDA  (Nuttall)  Gray,  Proc.  Am.  Acad.  19:49,  1883.    Plate  22. 
Stiff  Sagebrush. 

A  low  shrub,  4  dm.  or  less  high,  with  pungent  odor;  stems  thick  and  rigid,  much 
branched  from  near  the  base,  the  branches  spreading  or  erect,  forming  rounded  clumps, 
clothed  with  a  dark  fibrous  bark,  the  very  short  twigs  not  striate  but  canescent  or  gla- 
brate  and  then  yellowish;  principal  leaves  sessile,  spatulate  in  outline  but  with  narrowly 
linear  base,  1.5  to  4  cm.  long,  1  mm.  wide  below  the  lobes,  parted  or  cleft  from  the  summit 
into  3  to  5  narrowly  linear  lobes,  silvery-canescent  on  both  sides ;  upper  leaves  similar  and 
only  slightly  reduced,  sometimes  entire,  all  longer  than  the  heads;  inflorescence  a  leafy 
spike,  2  to  15  cm.  long,  less  than  1  cm.  broad  exclusive  of  leaves;  heads  homogamous, 
sessile  and  solitary  in  the  axils  or  the  upper  ones  somewhat  glomerate,  erect;  involucre 
campanulate,  4  to  5  mm.  high,  2.5  to  3.5  mm.  broad;  bracts  12  to  26,  the  short  outer  ones 
orbicular  to  elliptic  and  acute,  the  inner  elliptic  or  spatulate  and  very  obtuse,  with  a 
white-scarious  margin,  all  canescently  tomentulose;  ray-flowers  wanting;  disk-flowers  5 
to  15,  fertile,  corolla  funnelform,  deeply  and  acutely  5-toothed,  2  to  2.8  mm.  long, 
glandular  at  least  on  the  tube,  often  reddish;  style-branches  oblong,  truncate,  erose 
across  summit;  achenes  somewhat  prismatic,  4-  or  5-angled  or  with  4  or  5  ribs,  glabrous. 
{A.  trifida  /3  rigida  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:398,  1841.) 

On  rocky  ridges  and  plains,  western  Montana  to  eastern  Washington  and  Oregon. 
Type  locality,  plains  of  Lewis  (Snake)  River.  Collections :  Wild  Horse  Island,  Flathead 
Lake,  Montana,  Jones  (according  to  Jones,  Bull.  Univ.  Mont.  61:48,  1910);  type  collec- 
tion, Nuttall  (Or);  Seven  Devils  Mountains,  Washington  County,  Idaho,  September  9, 
1899,  Jones  (US);  Yakima  region,  Washington,  1882,  Brandegee;  bluffs  of  Snake  River, 
above  Wawawai,  Washington,  Piper  3814  (Gr,  NY);  eastern  Oregon,  Cusick  250 4  (Gr, 
UC,  NY,  US);  east  of  The  Dalles,  Oregon,  September  25,  1919,  Hall  (CI);  south  rim  of 
the  Grande  Ronde  Valley,  Union  County,  Oregon,  Eggleston  13664  (US). 

RELATIONSHIPS. 

This  is  apparently  an  offshoot  from  the  tridentata  group  of  species,  but  because  of 
the  absence  of  connecting  forms  its  exact  phylogeny  is  difficult  to  determine.  In  many 
respects  it  suggests  A.  tridentata  trifida,  especially  in  its  reduced  stature,  silvery  pubes- 
cence, and  cut  of  leaf.  The  achenes  are  essentially  prismatic  and  4-angled  as  in  other 
members  of  this  group.  The  reduction  in  size  and  inflorescence  that  is  so  evident  in 
trifida  is  here  carried  to  its  extreme,  the  plants  being  very  low  and  the  inflorescence 
narrowed  to  a  leafy  spike.  These  traits  suggest  a  direct  derivation  from  trifida,  and  this 
is  not  at  all  improbable.  In  addition  to  the  reductions  mentioned,  rigida  differs  in  its 
elongated  upper  leaves,  each  with  a  head  in  its  axil,  in  the  more  silvery  pubescence,  in 
details  of  habit,  and  in  its  adaptation  to  less  favorable  soil  and  climatic  conditions.  It 
is  not  a  successful  competitor  with  other  shrubby  Artemisias,  as  is  indicated  by  its 


154  GENUS   ARTEMISIA. 

restriction  to  poor,  stony  soils  over  a  limited  area  from  western  Montana  to  eastern 
Washington,  where  there  is  a  deficiency  of  rainfall  in  summer  and  the  winters  are  com- 
paratively cold  and  bleak. 

The  original  reference  of  this  species  to  a  variety  of  A.  trifida  by  Nuttall  was  due  to 
the  incomplete  nature  of  the  type  specimens.  These  were  in  leaf  only  and  were  thus 
wanting  in  the  only  characters  whereby  rigida  may  be  readily  distinguished. 

ECOLOGY  AND  USES. 

Artemisia  rigida  is  a  low  shrub  with  deciduous  leaves.  Its  stature  and  leaf  habit 
correspond  with  its  position  on  thin  or  stony  soil  under  a  low  rainfall.  It  frequently 
alternates  with  tridentata  where  deeper  soils  permit  the  growth  of  the  latter.  It  tends  to 
form  pure  communities  with  few  or  no  secondary  species. 

The  scant  foliage  is  browsed  somewhat  by  sheep,  but  it  is  so  well  protected  by  the 
stiff  branches  and  the  species  is  of  such  limited  distribution  that  A.  rigida  is  of  almost 
negligible  importance  as  a  browse  shrub.  It  is  probably  a  cause  of  hay-fever,  especially 
in  Oregon. 

28.  ARTEMISIA  PYGMAEA  Gray,  Proc.  Am.  Acad.  21 : 413,  1886.    Plate  22. 
Pigmy  Sagebrush. 

A  depressed  shrub  less  than  2  dm.  high,  the  odor  unknown;  stems  flexuous  at  base, 
with  numerous  short,  erect  branches,  the  old  bark  dark  brown  and  fibrous,  the  twigs 
pale  or  nearly  white,  not  striate,  puberulent;  principal  leaves  sessile,  oblong  to  obovate 
in  outline,  with  linear  base,  0.2  to  0.5  cm.  long,  pinnately  3-  to  7-parted  or  with  as  many 
divergent  teeth,  the  linear  segments  obtuse  but  mucronate,  rigid,  green,  nearly  glabrous, 
more  or  less  viscid;  upper  leaves  smaller,  3-parted  or  3-toothed,  those  of  the  inflores- 
cence mostly  entire  and  all  shorter  than  the  heads;  inflorescence  spike-like,  1  to  4  cm. 
(or  more?)  long,  about  0.5  cm.  broad;  heads  homogamous,  sessile,  erect;  involucre  at 
first  nearly  cylindric,  later  spreading  and  campanulate,  4  to  5  mm.  high,  about  3.5  to  4 
mm.  broad;  bracts  about  15  to  20,  all  similar  but  the  outer  ones  regularly  shorter, 
linear  or  linear-spatulate  and  obtuse,  or  the  outer  ones  lanceolate  and  somewhat  acute, 
yellowish-green,  with  narrow  and  very  thin  white-scarious  margins,  sparsely  villous  or 
nearly  glabrous;  ray-flowers  wanting;  disk-flowers  3  to  5  (or  more?),  fertile,  corolla 
turbinate,  4-  or  5-toothed,  2.5  to  3  mm.  long,  glandular  at  least  on  the  tube;  style- 
branches  flat,  truncate,  fimbriate  at  summit;  achenes  ellipsoid,  truncate  at  summit, 
obscurely  angled,  glabrous. 

Known  only  from  eastern  Nevada  and  western  Utah.  Type  locality,  Desert  region 
of  Nevada,  at  Fisk  [Fish]  Creek  near  Eureka.  Collections:  Type  collection,  August, 
1885,  Brandegee  (Gr,  UC);  Pioche,  Lincoln  County,  southeastern  Nevada,  August  31, 
1912,  Jones  (UC);  Ortons  Ranch,  Utah,  Jones  5984  (NY). 

RELATIONSHIPS. 
This  species  differs  from  all  others  of  its  group  in  having  the  lower  leaves  pinnately 
parted  into  lateral  lobes  instead  of  toothed  or  lobed  from  the  summit.  Some  of  the 
upper  leaves,  however,  are  3-lobed,  very  much  after  the  manner  of  the  other  species. 
The  ribs  of  the  leaf  are  quite  prominent  in  the  type  collection,  but  in  others  they  are 
no  more  conspicuous  than  they  are  in  some  forms  of  A.  tridentata  (for  example,  in  sub- 
species trifida  as  represented  by  M.  E.  Jones's  Oroville,  Washington,  collection.  Herb. 
Univ.  Calif.  175975).  The  aspect  of  the  plant  is  unique  in  Artemisia.  The  low  tufted 
stems,  the  minute  rigid  foliage,  and  the  greenish  imbricated  involucres  suggest  the 
appearance  of  an  Haplopappus  of  the  Ericameria  section.  The  technical  characters 
relate  it  to  .4.  tridentata  and  A.  rigida,  but  beyond  this  its  phylogenetic  origin  can  not 
now  be  determined. 


A.    PALMERI.  155 

ECOLOGY  AND  USES. 
Artemisia  pygmaea  is  a  dwarf  shrub  with  greatly  reduced  leaves,  corresponding  with 
its  climatic  position  and  its  habitat  in  alkaline  areas,  where  it  is  associated  with  the 
halophytic  Chrysotha-pinus  nauseosus  consimilis.     Its  small  size  and  rare  occurrence 
preclude  any  uses. 

29.  ARTEMISIA  PALMERI  Gray,  Proc.  Am.  Acad.  11:79,  1876.    Plate  23. 
Tall  Sagebrush. 

A  shrub  12  to  30  dm.  high,  with  straight,  wand-like  herbaceous  stems  that  commonly 
make  clusters  about  10  dm.  across,  the  habit  then  similar  to  that  of  A.  ahrotanum,  or 
sometimes  in  younger  plants  the  stems  few  or  solitary,  nearly  simple,  and  more  her- 
baceous, the  odor  strong,  but  not  unpleasant;  flowering  stems  erect,  conspicuously 
striate,  glabrous  or  minutely  puberulent,  reddish;  principal  leaves  petioled  or  sessile  by 
a  narrow  base,5  to  15  cm. long,  pinnately  parted  into  3  to  5  long  linear  lobes  with  closely 
revolute  margins  or  entire  and  linear,  green  and  glabrous  or  minutely  puberulent  above, 
densely  white-tomentose  beneath;  upper  leaves  similar  but  more  of  them  entire,  nearly 
wanting  in  the  inflorescence;  inflorescence  an  open  terminal  pyramidal  panicle,  15  to  40 
cm.  long,  3  to  10  cm.  broad;  heads  homogamous,  on  peduncles  1  to  5  mm.  long  or  some- 
times sessile,  mostly  nodding  at  maturity;  involucre  hemispheric,  3  to  4  mm.  high, 
2  to  3.5  mm.  broad;  bracts  7  to  12  (and  in  addition  10  to  20  elliptic  obtuse  bracts  scat- 
tered among  the  flowers),  ovate,  acutish,  the  outer  ones  but  little  shorter  than  the  inner, 
sparingly  pubescent  or  glabrous,  scarious-margined ;  ray-flowers  wanting;  disk-flowers 
12  to  25  or  rarely  up  to  35,  fertile,  corolla  narrowly  funnelform  or  nearly  tubular,  5- 
toothed,  1.5  to  2.2  mm.  long,  glandular-granuliferous  especially  on  the  tube;  style- 
branches  flat,  truncate  and  erose  at  summit  (sometimes  described  as  included  but 
long-exserted  and  coiled  at  maturity  in  most  specimens) ;  achenes  nearly  prismatic  but 
slightly  narrowed  below,  4-angled,  the  summit  truncate,  granuliferous. 

Southwestern  San  Diego  County,  California  and  northern  Lower  California.  Type 
locaUty,  San  Diego  County,  California,  in  Jamul  Valley,  20  miles  east  of  San  Diego. 
Collections:  Type  collection,  1875,  Palmer  (Gr,  NY  as  No.  193);  near  San  Diego,  1899, 
Purpus  (UC,  Phila);  same  locality,  September  9,  1899,  Brandegee  (Pomona  College 
Hb.);  near  National  City,  Brandegee  (UC,  US);  Oneonta,  San  Diego  County,  July,  1900, 
Brandegee  (Phila);  Alpine,  San  Diego  County,  August  6,  1894,  M earns  3942  (US);  bluffs 
near  the  sea.  La  JoUa,  Ahrams  4013  (DS,  Gr,  NY);  All  Saints  Bay,  Lower  California, 
July,  1882,  Fish  (Gr). 

SYNONYM. 

1.  Artemisiastrum  PALMERI  Rydbefg,  N.  Am.  Fl.  34:285,  1916. — A.  palmeri. 
RELATIONSHIPS. 

The  relationships  of  this  species  are  exceptionally  obscure.  The  presence  of  chaff  on 
the  receptacle  is  not  known  elsewhere  in  Artemisia  and  it  was  principally  because  of  this 
that  Rydberg  recently  set  the  species  aside  as  a  new  genus,  namely,  Artemisiastrum  (N. 
Am.  Fl.  34:285,  1916).  The  objections  to  this  treatment  have  been  stated  earlier  in  this 
paper  (p.  33).  Aside  from  this  character,  A.  palmeri  plainly  goes  into  the  section  Seri- 
p/iiditzTO,  although  it  differs  from  all  of  the  other  members  of  this  section  in  several  details. 
No  other  American  species  has  such  elongated  herbaceous  branches,  although  true  herbs 
are  common  among  Old  World  species;  the  cut  of  the  leaf  and  the  peduncled  heads  are 
more  suggestive  of  A.  dracunculus  or  of  certain  forms  of  A.  vulgaris  than  of  any  member 
of  the  section  Seriphidium;  and  the  involucral  bracts  are  more  nearly  equal  in  size  than 
in  other  species,  while  at  the  same  time  their  number  is  greatly  reduced.  It  is  possible 
that  some  of  the  bracts  on  the  outer  part  of  the  disk  are  in  reality  bracts  of  the  involucre 
which  have  taken  up  a  more  central  position,  but  the  number  is  sometimes  too  great  to 


156 


GENUS   ARTEMISIA. 


be  accounted  for  in  this  way.  As  far  as  examined,  each  bract  subtends  one  of  the  disk- 
flowers.  When  the  latter  are  numerous,  some  of  them  are  devoid  of  bracts.  It  therefore 
seems  more  reasonable  to  look  upon  the  presence  of  receptacular  bracts  as  a  case  of 
reversion.  This  is  not  due  to  the  persistence  of  an  ancestral  trait,  as  is  evident  from  the 
high  position  of  Seriphidium  within  the  genus  and  from  the  absence  of  these  structures 
in  immediately  related  genera  many  of  which  are  more  primitive  than  Artemisia. 

Since  no  one  of  the  American  Seriphidia  approaches  A.  palmeri,  its  relationships  are 
perhaps  to  be  sought  in  the  Old  World,  and  this  must  be  left  for  later  studies.  A  possible 
alternative  is  its  evolution  from  some  group  of  the  section  Abrotanum.  The  habit,  cut 
of  leaf,  and  other  features  are  very  suggestive  of  A.  vulgaris  mexicana,  but  a  derivation 
from  this  group  would  involve  at  once  the  loss  of  ray-flowers,  the  development  of  recep- 
tacular bracts,  and  a  change  in  the  shape  of  the  achenes  in  addition  to  minor  changes. 
This  connection  is  therefore  scarcely  more  than  a  remote  possibility. 

As  compared  with  most  Artemisias,  the  achene  more  closely  approaches  a  truly  pris- 
matic shape.  It  is  even  more  decidedly  quadrangular  and  evenly  truncate  at  summit 
than  in  other  species  of  the  section  Seriphidium,  where  subprismatic  achenes  are  the  rule. 
Although  sharply  4-angled,  the  achene  is  not  otherwise  ribbed  or  crowned,  as  sometimes 
described.  The  characters  of  the  corolla,  even  down  to  the  peculiar  glandular-granu- 
liferous  tube  and  the  style-branches,  are  as  in  other  members  of  its  section.  Other  char- 
acters are  indicated  in  the  subjoined  table. 

ECOLOGY  AND  USES. 

Artemisia  palmeri  is  a  tall  shrub  with  more  or  less  herbaceous  branches.  It  forms  a 
sparse  consocies  in  ravines  and  along  moist  banks,  and  also  pushes  a  short  distance  up 
slopes,  where  it  meets  A.  calif ornica  and  its  associates. 

It  is  rare  and  local,  and  hence  has  not  been  used,  though  its  odor  suggests  that  it  may 
possess  the  value  of  certain  European  species  for  flavoring. 


Table  16. — Variation  in  Artemisia  palmeri. 


No.  of 
bracts  of 
receptacle. 


No.  of 
flowers. 


Length 
of  disk- 
corolla. 


San  Diego  County,  Calif,  (type) . 

Near  San  Diego,  Calif 

National  City,  Calif 

La  JoUa,  Calif 

Alpine,  Calif 

All  Saints  Bay,  Lower  Calif 


Gr 

29705  UC 
91220  UC 

Gr 
239844  US 

Gr 


Average . 


2.0  2.5 
3.5 

25  30 
2.0 

2.1  2.5 
2.0  3.0 

2.5 


9 

10     10 

10       9 

11 


Explanations  of  Plates  1  to  23,  Genus  Artemisia. 


Plate  1. 

Artemisia  abrolanum.  (Drawn  from  material  collected 
in  Virginia  from  an  introduced  plant,  29718 
UC;  supplemented  by  foliage  from  a  plant 
in  the  Botanical  Garden  of  the  University 
of  California.) 

(1)  Erect  shoot  showing  the  narrow  leaf-lobes  and 

the  broad  inflorescence,  X  1. 

(2)  Young  head,  X  8. 

(3)  Outer  bract  of  the  involucre,  X  16. 

(4)  Middle  bract,  X  16. 

(5)  Inner  bract,  X  16. 

(6)  Ray-flower,    showing    a    few    glands    on    the 

corolla,  X  16. 

(7)  Style-branches  of  a  ray-flower,  X  24. 

(8)  Disk-flower  with   a  few  resin-glands  on  the 

achene  and  corolla,  X  16. 

(9)  Style  of  the  disk-flower  showing  the  truncate 

tips,  X  24. 
Artemisia  pontica.     (Dra\vn  from  material  collected 
in  Europe,  161793  UC). 

(10)  Erect  stem  showing  the  finely  pinnatifid  foliage 

and  the  elongated  inflorescence,  X  1. 

(11)  Mature  head,  X  8. 

(12)  Outer  bract  of  the  involucre,  X  16. 

(13)  Inner  bract,  X  16. 

(14)  Ray-flower    showing    the    irregularly    angled 

achene,  X  16. 

(15)  Style  of  the  ray-flower,  X  24. 

(16)  Disk-flower  showing  the  broad-topped,  angular 

achene,  X  16. 

(17)  Style  of  the  disk-flower  showing  the  truncate 

and  penicillate  branches,  X  24. 
Plate  2. 
Artemisia  californica.     (Drawn  from  fresh  material, 
Oakland  Hills,  California,  except  the  leaves 
of  fig.  12.) 

(1)  Inflorescence,  X  1. 

(2)  Habit    of   plant    as    normally    developed    on 

gentle  slopes,  X  0.07. 

(3)  Ray-flower,  X  16. 

(4)  Style  of  ray-flower,  X  24. 

(5)  Disk-flower,  X  16. 

(6)  Style  of  disk-flower,  X  24. 

(7)  Head,  X  8. 

(8)  Outer  bract  of  the  involucre,  X  16. 

(9)  Middle  bract,  X  16. 

(10)  Inner  bract,  X  16. 

(11)  Leaves  showing  variation  in  lobing,  all  from  a 

single  platit;  most  of  the  leaves  are  entire  or 
only  once  pinnatifid;  X  1. 

(12)  Leaves  of  an  insular  form  described  under  minor 

variation  7,  X  1.     (Material  from  San  Cle- 
mente  Island,  California,  UC.) 
Plate  3. 
Artemisia  norvegica  heterophylla.  (Material  from  Mount 
Rainier,  Washington,  9776  UC.) 

(1)  Stem  with  leaves  and  inflorescence,  X  1. 

(2)  Disk-flower,  X  16. 

Artemisia  norvegica  globidaria.  (Material  from  St.  Paul 
Island,  Alaska,  73910  UC.) 

(3)  Stem  with  leaves  and  inflorescence,  X  1. 

(4)  Disk-flower,  X  16. 

Artemisia  norvegica  glomerata.  (Material  from  Aia- 
kamtchetchene  Island,  Bering  Sea,  Or.) 

(5)  Stem  with  leaves  and  inflorescence,  X  1. 

(6)  Disk-flower,  X  16. 

Artemisia  norvegica  saxatilis.  (Material  from  Pyramid 
Peak,  California,  54076  UC.) 

(7)  Stem  with  basal  leaves  and  a  portion  of  the 

inflorescence,  X  1. 


Plate  3 — continued. 

(8)  Ray-flower,  X  16. 

(9)  Outer  bract  of  the  involucre,  X  16. 

(10)  Inner  bract,  X  16. 

(11)  Head,  X  8. 

(12)  Disk-flower,  X  16. 

(13)  Style  of  disk-flower,  X  24. 
Plate  4. 

Artemisia  parryi.     (Drawn  from  type  specimen,  Gr.) 

(1)  Stem  showing  leaves  and  inflorescence,  X  1. 

(2)  Outer  bract  of  the  involucre,  X  16. 

(3)  Middle  bract,  X  16. 

(4)  Rav-flower,  X  16. 

(5)  Disk-flower,  X  16. 

(6)  Style  of  a  disk-flower,  X  24. 

(7)  Head,  X  8. 

Artemisia  senjaviTiensis.    (Material  from  Arakamtchet- 
chcne  Island,  Bering  Sea,  Gr.  US.) 

(8)  Portion  of  a  mat,  showing  stem,  leaves,  and 

inflorescence,  X  1. 

(9)  Leaf,  showing  lobes,  X  2. 

(10)  Head,  X  8. 

(11)  Ray-flower,  X  16. 

(12)  Disk-flower,  X  16. 

(13)  Style  of  a  disk-flower,  X  24. 

Artemisia  macrobolrys.      (Material  from  above   Fort 
Selkirk,  Yukon,  Tarleton,  NY.) 

(14)  Leaf  showing  the  divergent  lobes,  X  1. 

(15)  Ray-flower,  X  16. 

(16)  Disk-flower,  X  16. 

(17)  Style  of  a  disk-flower,  X  24. 

(18)  Head,  X  8. 
Plate  5. 

Artemisia  stelleriana.     (Material  from  Ocean  Beach, 
Massachusetts,  193468  UC.) 

(1)  Shoot  and  inflorescence,  X  1. 

(2)  Style  of  ray-flower,  X  24. 

(3)  Ray-flower,  X  16. 

(4)  Disk-flower,  X  16. 

(5)  Style  of  disk-flower,  X  24. 

(6)  Outer  bract  of  the  involucre,  X  16. 

(7)  Middle  bract,  X  16. 

Artemisia  alaskana.     (Drawn  from  a  portion  of  the 
type  specimen,  NY.) 
(81  Section  of  the  inflorescence,  showing  the  long 

peduncles,  X  1. 
(91  Various  types  of  leaves  from  same  plant,   X  1. 
(101  Ray-flower,  X  16. 

(11)  Style  of  ray-flower,  X  24. 

(12)  Disk-flower,  X  16. 

(131  Style  of  disk-flower,  X  24. 
Plate  6. 
Artemisia  franserioides.     (Drawn  from  fresh  material 
and  photo,  from  San  Juan  Mountains,  Colo.) 

(1)  Inflorescence  showing  the  secund  arrangement 

of  the  heads,  X  1. 

(2)  A  pair  of  lower  leaves,  X  1. 

(3)  Habit  sketch  of  an  entire  plant,  X  0.1. 

(4)  Inner  bract  of  the  involucre,  X  16. 

(5)  Outer  bract,  X  16. 

(6)  Head,  X  8. 

(7)  Ray-flower,  X  16. 

(8)  Style  of  ray-flower,  X  24. 

(9)  Disk-flower,  X  16. 

(101  Style  of  disk-flower,  X  24. 

(11)  Principal  leaf  from  near  base  of  stem,  showing 

the  obtuse  lobes,  XI. 
Artemisia  vulgaris  serrala.     (Material  from  northern 
Illinois,  193540  UC.) 

(12)  Portion  of  inflorescence  and  a  leaf  from  lower 

down  on  the  stem,  X  1. 


Explanations  of  Plates  1  to  23,  Genus  Artemisia. 


Plate  7. 
Artemisia  vulgaris  tilesi  (the  tall  form,  =  A.  elatior). 
(Material    from    the    Idondyke    River    at 
Dawson,  Canada,  SF.) 

(1)  Inflorescence;  this  much  more  elongated  and 

with  smaller  heads  than  in  typical  tilesi,  X  1. 

(2)  Leaf  from  middle  portion  of  the  stem,  X  1. 
Artemisia  tndgaris  typica.     (Material  from  along  St. 

John  River,  Maine,  29797  UC,  the  detached 
leaves  from  near  Andover,  New  Jersey, 
29801  UC.) 

(3)  Inflorescence,  X  1. 

(4)  Lower  leaf,  X  1. 

(5)  Middle  cauline  leaf,  X  1. 

(6)  Upper  cauline  leaf,  X  1 . 

(7)  Cluster  of  leaves  from  the  same  stem  as  3,  X  1. 

(8)  Disk-flower,  X  16. 

(9)  Style  of  disk-flower,  X  24. 

(10)  Head,  X  8. 

(11)  Style  of  ray-flower,  X  24. 

(12)  Ray-flower,  X  16. 

(13)  Outer  bract  of  the  involucre,  X  16. 

(14)  Inner  bract,  X  16. 

Plate  8. 
Artemisia     vulgaris    heterophylla.     (Drawn     from     a 
living  plant,  Berkeley,  California.) 

(1)  Upper  portion  of  the  inflorescence,  X  1. 

(2)  Habit  sketch  of  a  portion  of  a  plant;  the  low 

shoots  are  from  rootstocks  connected  below 
the  surface  with  the  larger  stems;  X  0.03. 

(3)  Series  of  leaves  so  arranged  as  to  preserve  the 

original  sequence  up  the  stem,  X  1. 

(4)  Lower  leaf  from  the  same  plant  but  gathered 

earlier  in  the  season,  X  1. 

(5)  Disk-flower,  X  16. 

(6)  Style  of  disk-flower,  X  24. 

(7)  Ray-flower,  X  16. 

(8)  Style  of  ray-flower,  X  24. 

(9)  Head,  X  8. 

(10)  Middle  bract  of  the  involucre,  X  16. 

(11)  Inner  bract,  X  16. 

Plate  9. 

Artemisia  vulgaris  gnaphalodes.     (Drawn  from  fresh 
material  from  Reno,  Nevada.) 

(1)  Inflorescence  and  a  portion  of  the  leafy  stem, 

showing  lobed   leaves  in   the   middle,   with 
entire  ones  both  below  and  above,  X  1. 
Artemisia  vtdgaris  wrighti.     (Drawn  from  fresh  material 
from  Colorado  Springs,  Colorado.) 

(2)  Top  of  plant  with  inflorescence,  X  1. 

(3)  Head,  X  8. 

(4)  Outer  bract  of  the  involucre,  X  16. 

(5)  Inner  bract,  X  16. 

(6)  Ray-flower,  X  16. 

(7)  Style  of  ray-flower,  X  24. 

(8)  Disk-flower,  X  16. 

(9)  Style  of  disk-flower,  X  24. 

Artemisia  bigelovi.     (Drawn  from  fresh  material  from 
Caflon  City,  Colorado.) 

(10)  Main  portion  of  stem  with  inflorescences,  X  1. 

(11)  Outer  bract  of  the  involucre,  X  16. 

(12)  Inner  bract,  X  16. 

(13)  Head,  X  8. 

(14)  Ray-flower,  X  16. 

(15)  Style  of  ray-flower,  X  24. 

(16)  Disk-flower,  X  16. 

(17)  Style  of  disk-flower,  X  24. 


Plate  10. 
Artemisia  annua.     (Material  from  St.  Louis,  Missouri, 
193447  UC.) 

(1)  Inflorescence,  X  1. 

(2)  Leaves  from  middle  portion  of  the  stem,  X  1. 

(3)  Ray-flower,  X  16. 

(4)  Style  of  ray-flower,  X  24. 

(5)  Disk-flower,  X  16. 

(6)  Style  of  disk-flower,  X  24. 

(7)  Head,  X  8. 

(8)  Outer  bract  of  the  involucre,  X  16. 

(9)  Inner  bract,  X  16. 

Artemisia  klotzschiana.  (Material  from  Pachuca, 
Hidalgo,  135382  UC.) 

(10)  Upper  portion  of  inflorescence,  X  1. 

(11)  Middle  portion  of  stem,  with  leaves,  X  1. 

(12)  Head,  X  8. 

(13)  Outer  bract  of  the  involucre,  X  16. 

(14)  Inner  bract,  X  16. 

(15)  Ray-flower,  X  16. 

(16)  Style  of  ray-flower,  X  24. 

(17)  Disk-flower,  X  16. 

(18)  Style  of  disk-flower,  X  24. 

Artemisia  biennis.  (Drawn  from  living  plants, 
Berkeley,  California.) 

(19)  Principal  leaves  from  middle  part  of  stem,  X  1. 

(20)  Upper  portion  of  inflorescence,  X  1. 

(21)  Head,  X  8. 

(22)  Outer  bract  of  the  involucre,  X  16. 

(23)  Inner  bract,  X  16. 

(24)  Ray-flower,  X  16. 

(25)  Style  of  ray-flower,  X  24. 

(26)  Disk-flower,  X  16. 

(27)  Style  of  disk-flower,  X  24. 

(28)  Habit  sketch,  X  0.025. 

Plate  11. 
Artemisia  absinthium,     (Drawn  from  living  material 
from   the   Botanical  Garden,   University  of 
Cahfornia.) 

(1)  Portion  of  shoot  and  inflorescence,  X  1. 

(2)  Disk-flower,  X  16. 

(3)  Style  of  disk-flower,  X  24. 

(4)  Head,  X  8. 

(5)  Narrow  outer  bract  of  the  involucre,  X  16. 

(6)  One  of  the  principal  bracts,  X  16. 

(7)  Style  of  ray-flower,  X  24. 

(8)  Ray-flower,  X  16. 

Artemisia  frigida.  (Drawn  from  living  material  grow- 
ing near  Manitou,  Colorado;  the  details  from 
material  collected  on  the  Laramie  Plains, 
Wyoming.) 

(9)  Inflorescence,  X  1. 

(10)  Leaf  from  midwav  up  the  stem,  X  1. 

(11)  Head,  X  8. 

(12)  Outer  bract  of  the  involucre,  X  16. 

(13)  Inner  bract,  X  16. 

(14)  Rav-flower,  X  16. 

(15)  Style  of  ray-flower,  X  24. 

(16)  Disk-flower,  X  16. 

(17)  Style  of  disk-flower,  X  24. 

(18)  Habit  sketch  of  an  entire  plant,  X  0.125. 

Plate  12. 
Artemisia  pattersoni.  (Drawn  from  fresh  material 
from  Pike's  Peak,  Colorado.) 
(1)  Entire  plant,  X  1.  The  details  of  heads  and 
flowers  are  similar  to  those  of  A.  scopulorum, 
except  that  the  parts  are  larger  and  the 
corollas  glabrous. 


Explanations  of  Plates  1  to  23,  Genus  Artemisia. 


Plate  12 — continued. 
Artemisia  scopulorum.     (Drawn  from  fresh  material 
from  Pike's  Peak,  Colorado,  except  fig.  2.) 

(2)  Entire  plant  of  a  much  reduced  alpine  form 

from  La  Sal  Mountains,  Utah  (175205 
UC);  X  1. 

(3)  Average  plant,  X  1. 

(4)  Ray-flower,  X  16. 

(5)  Style  of  ray-flower,  X  24. 

(6)  Disk-flower,  X  16. 

(7)  Style  of  disk-flower,  X  24. 

(8)  Head,  X  8. 

(9)  Outer  bract  of  the  involucre,  X  16. 
(10)  Inner  bract,  X  16. 

Plate  13. 

Artemisia   dracunculus    typica.     (Drawn    from    living 
plants  in  eastern  Colorado.) 

(1)  Upper  portion  of  inflorescence,  X  1. 

(2)  Lower  portion  of  stem,  with  foliage,  X  1. 

(3)  Habit  sketch  of  a  portion  of  a  plant,  X  0.1 

(4)  Outer  bract  of  the  involucre,  X  16. 

(5)  Inner  bract,  X  16. 

(6)  Ray-flower,  X  16. 

(7)  Style  of  ray-flower,  X  24. 

(8)  Disk-flower,  X  16. 

(9)  Style   of   disk-flower,   showing   2   very   short 

lobes;  X  24. 

(10)  Style  of  disk-flower,  showing  deeper  cleavage; 

X24. 

(11)  Head,  X  8 
Plate  14. 

Artemisia  campestris  typica.     (Material  from  Branden- 
burg, 6488  Baker  Herb.) 

(1)  Inflorescence,  X  1.     The  details  of  the  heads 

and  flowers  are  identical  with  those  of  sub- 
species pacifica. 
Artemisia    campestris    pacifica.     (Drawn    from    fresh 
material  from  Manitou,  Colorado.) 

(2)  Inflorescence,  X  1.     The    two    portions    were 

continuous;  other  inflorescences  on  the  same 
plant  were  more  widely  branched,  but  the 
branches  were  all  close  and  more  nearly 
erect  than  in  fig.  1. 

(3)  Habit  sketch,  X  0.1. 

(4)  Basal  leaf,  X  1. 

(5)  Head,  X  8. 

(6)  Outer  bract  of  the  involucre,  X  16. 

(7)  Inner  bract,  X  16. 

(8)  Ray-flower,  X  16. 

(9)  Style  of  ray-flower,  X  16. 

(10)  Disk-flower,  X  16. 

(11)  Style  of  disk-flower,  X  24. 
Plate  15. 

Artemisia  campestris  borealis. 

(1)  A    plant    with    a    narrow    inflorescence,  X  1. 

(Material  from  Mount  Albert,  eastern 
Quebec,  147968  UC.) 

(2)  A   more    spreading    inflorescence,    see    minor 

variations,  X  1.  (Material from  Mount Ste. 
Abbe,  Gaspe  County,  Quebec,   69740  UC.) 

(3)  Basal  leaves  from  the  same  plant  as  fig.  2,  X  1. 

(4)  Habit    sketch    of    the    plant    represented    in 

figs.  2  and  3,  X  0.14. 
Artemisia     campestris     spithamaea.     (Material     from 
Saguache  Mountains,  Utah,  91237  UC.) 

(5)  Style  of  disk-flower,  showing  cleavage  on  one 

side,  X  24.  The  style-branches  are  com- 
pletely fused  in  most  of  the  flowers. 


Plate  15 — continued. 

Artemisia  campestris  pycnocephala.  (Drawn  from 
fresh  material  from  Carmel,  California.) 

(6)  Upper  portion  of  the  inflorescence,  X  1. 

(7)  Head,  X  8. 

(8)  Ray-flower,  X  16. 

(9)  Style-branch  of  ray-flower,  X  24. 

(10)  Disk-flower,  X  16. 

(11)  Style-branch  of  disk-flower,  X  24. 

(12)  Leaf,  X  1. 

Plate  16. 

Artemisia  pedatifida.  (Material  from  western  Wyo- 
ming; partly  fresh,  partly  herbarium  speci- 
mens.) 

(1)  Portion  of  a  plant,  showing  habit  and  inflores- 

cence, X  1. 

(2)  Leaf,  X  3. 

(3)  Outer  bract  of  the  involucre,  X  16. 

(4)  Inner  bract,  X  16. 

(5)  Head,  X  8. 

(6)  Style-branch  of  ray-flower,  X  24. 

(7)  Ray-flower,  X  16. 

(8)  Disk-flower,  X  16. 

(9)  Style    of    disk-flower,    showing    the    distinct 

branches,  X  24. 

(10)  Style   of   disk  flower,    showing   the   branches 

fused  along  one  side;  X  24. 
Artemisia  filifolia.     (Drawn  from  fresh  material  from 
Caiion  City,  Colorado,  the  details  from  Will- 
co.\  Flat,  Arizona,  195188  UC.) 

(11)  Upper  portion  of  stem  and  inflorescence,  X  1. 

(12)  Style  of  disk-flower,  X  24. 

(13)  Disk-flower,  X  16. 

(14)  Head,  X  8. 

(15)  Style  of  ray-flower,  X  24. 

(16)  Ray-flower,  X  16. 

(17)  Outer  bract  of  the  involucre,  X  16. 

(18)  Inner  bract,  X  16. 

Plate  17. 
Artemisia  spinescens.     (Material  from  sandy  benches 
near  Barstow,  California,  126503  UC,  except 
fig.  2.) 

(1)  Branch  showing  spiny  habit  and  the  arrange- 

ment of  the  heads,  X  1. 

(2)  Habit  sketch,  X  0.125. 

(3)  Leaves  showing  different  degrees  of  lobing,  X  3. 

(4)  Ray-flower,  showing  the  loose  pubescence  of 

the  achene  and  corolla;  X  16. 

(5)  Style  of  ray-flower,  X  24. 

(6)  Head,  X  8. 

(7)  Inner  bract  of  the  involucre,  X  16. 

(8)  Outer  bract  of  the  involucre,  X  16. 

(9)  Disk-flower,  showing  the  loose  pubescence  of 

the  corolla;  X  16. 
(10)  Style  of  disk-flower,  X  24. 
Plate  18. 
Artemisia  tridentata  typica.     (Drawn  from  fresh  ma- 
terial from  northwestern  New  Mexico.) 

(1)  Typical  inflorescence,  X  1. 

(2)  Leafy  shoot,  showing  tridentate  leaves,  X  1- 

(3)  Head,  X  8. 

(4)  Outer  bract  of  the  involucre,  X  16. 

(5)  Inner  bract,  X  16. 

(6)  Flower  with  scattered  resin-granules,  X  16. 

(7)  Style,  X  24. 

(8)  Habit  sketch  of  a  common  form,  from  a  photo- 

graph of  a  plant  at  Wells,  Nevada;  X  0.04. 


Explanations  of  Plates  1  to  23,  Genus  Artemisia. 


Plate  18 — continued. 

Artemisia  tridcntata  parishi.       (Drawn  from  fresh  ma- 
terial from  the  tv-pe  locality,  except  the  flower, 
which  is  from  type  collection,  54010  UC.) 
(9)  Leafy  shoot  with  entire,  bidentate,  and  triden- 
tate  leaves,  X  1. 

(10)  Portion  of  a  younp  inflorescence  with  drooping 

heads,  X  1.  The  heads  on  neighboring  plants 
are  erect,  as  in  the  usual  form  of  typica 
(see  p.  143). 

(11)  Flower    showing    the  pubescent  achene  and 

scattered  resin-granules,  X  16. 

Plate  19. 
Artemisia  tridentata  trifida.     (Drawn  from  fresh  ma- 
terial from  southern  Wyoming.) 

(1)  Branch  showing  the  mostly  trifid  leaves  and 

narrow  inflorescences,  X  1. 

(2)  Habit  sketch,  X  0.08. 

Artemisia  tridentata  nova.      (Material  from   Laramie 
Hills,  Wyoming,  517G0  UC.) 

(3)  Branch    showing   the    tridentate    leaves   and 

moderately  narrow  inflorescences,  X  1. 

(4)  Shoot    with    some    leaves    tridentate,    others 

trifid,  X  1. 

(5)  A  very  narrow  inflorescence,  X  1. 

(6)  Head,  X  8. 

(7)  Outer  bract  of  the  involucre,  X  16. 

(8)  Inner  bract,  X  16. 

(9)  Flower  with  scattered  resin-granules,  X  16. 
(10)  Style,  X  24. 

Plate  20. 
Artemisia  tridentata  arbuscula. 

(1)  Leafy  shoot  with  2  inflorescences,  X  1.     (Ma- 

terial from  eastern  Oregon,  175216  UC.) 

(2)  Leafy  shoot  showing  the  more  deeply  lobed 

leaves  of  minor  variation  10  (p.   140),  X  1. 
(Material   from   near   Donner   Pass,    Placer 
County,  California,  202223  UC.) 
Artemisia  tridentata  rothrocki. 

(3)  Stem  with  narrow  inflorescence,  X  1.     (Ma- 

terial from  Tioga  Pass,  California.) 

(4)  Leafy    shoot,  X  1.       (Material    from    Little 

Cottonwood  Creek,  California.) 

(5)  Stem  with  typical  branching  inflorescence,  X  1. 

(From  the  same  plant  as  fig.  4.) 

Plate  21. 
Artemisia  carta.     (Drawn  from  fresh  material  from 
Bosler,  Wyoming.) 

(1)  Branch  with  leafy  shoots,  X  1. 

(2)  Inflorescence,  X  1. 


Plate  21 — continued. 

(3)  Inflorescence  showing  more  elongated  branches, 

X  1. 

(4)  Shoot  with  leaves  of  maximum  width,' X  1. 

(5)  Head,  X  8. 

(6)  Middle  bract  of  the  involucre,  X  16. 

(7)  Inner  bract,  X  16. 

(8)  Flower,  X  16. 

(9)  Style,  X  24. 

(10)  Habit  sketch,  X  0.03. 

Plate  22. 
Artemisia  rigida.     (Drawn  from  fresh  material  and 
photographs  from  northeastern  Oregon.) 

(1)  Portion  of  plant  with  inflorescences,  X  1. 

(2)  Head,  X  8. 

(3)  Bract  from  the  base  of  tlie  involucre,  X  16. 

(4)  Inner  bract,  X  16. 

(5)  Flower,  X  16. 

(6)  Style,  X  24. 

(7)  Three  leaves,  showing  variation  in  lobing;  X  3. 

(8)  Leaf  of  the  inflorescence,  X  3. 

(9)  Habit  sketch  of  entire  plant,  X  0.125. 
Artemisia  pygmaea.     (Material  from  Pioche,  Nevada, 

17947S  UC.) 

(10)  Twigs,  showing  the  inflorescence;  X  1. 

(11)  Leaves,  X  3. 

(12)  Habit  sketch,  apparently  of  a  plant  growing 

on  a  slope,  since  the  roots  are  horizontal; 
X  0.17. 

(13)  Inner  bract  of  the  involucre,  X  16. 

(14)  Bract  from  outer  portion  of  the  involucre,  X  16. 

(15)  Flower,  X  16. 

(16)  Style,  X  24. 

(17)  Head,  X  8. 

Plate  23. 

Artemisia  palmeri.    (Drawn  from  fresh  material  from 
La  Jolla,  Cahfornia.) 

(1)  Portion   of   the   inflorescence   showing  also   a 

few  of  the  entire  upper  leaves,  X  1. 

(2)  A  common  type  of  leaf  with  five  lobes,  X  1. 

(3)  An  upper  leaf  with  three  lobes,  X  1. 

(4)  An    upper    leaf    with    a   single    lateral    lobe, 

transitional    to    the    simple    leaves  of    the 
inflorescence;  X  1. 

(5)  Head  with  subtending  bracts,  X  8. 

(6)  Outer  bract  of  the  involucre,  X  16. 

(7)  Inner  bract,  X  16. 

(8)  Disk-flower  showing  scattered  resin-glands  on 

the    achene    and    corolla,  X  16.      The    ray- 
flowers  are  wanting  in  this  species. 

(9)  Style,  X  24. 


HALL  AND  CLEMENTS 


%n 


:':i' 


/ 


^^ 


■  7  -'•% 


r-.- 


HALFTONES  BY 
LANMAN  ENCK.CO. 
WASH.  DC. 


Kulh   J.   Pmvrll  del. 


Artemisia  abrotanum.  figs.  1  to  •).  ArtPinisia  ponlioa.  Iigs.  10  to  T 


HALL  AND  CLEMENTS 


Hulh  J.  Powell  del. 


Artemisia  californica. 


HALL  AND  CLEMENTS 


9  -r^W^-^         10 


Kulh   J.   P<m;U  M. 


Artemisia  iKiivc^nca  lictcrdphvlla.  fijjs.  1  aiui 
Artemisia  norve^^ica  jrlobiilaria,  fifjs.  '.'>  and  4. 


Artemisia  norvefjica  j^'ioinerata,  figs.  5  and  6. 
Artemisia  norvegica  saxatilis.  figs.  7  to  i:5. 


HALL  AND  CLEMENTS 


Hulh  J.  Pau-cll  dfl. 

Artemisia  parryi,  figs,  1  to  7.        Artemisia  senjavinensis,  figs.  8  to  13.  Artemisia  macrobotrys,  figs.  14  to  18. 


HALL  AND  CLEMENTS 


m 


^^m 


-^ 


fk 


•iull,   J.    Pmnll  ,1,1. 


Artemisia  sti'llt'tiana.  figs.  I  t( 


ArtPinisia  aiaskana.  fif-'s.  8  to  i:5. 


tuth   J.   Pouell  •Id. 


Artemisia  franserioides,  figs.  I  to  11. 


Artemisia  vulgaris  sen 


HALL  AND  CLEMENTS 


mL  '4  ■[  iK^f^ 


I 


'^'1    3 


\rleinisia  vulgaris  tilesi.  figs.  1  and  2.  Aileniisia  vulgaiis  typica.  figs.  3  to  14. 


HALL  AND  CLEMENTS 


Rulh   J    I'lmrll  ,lrl 


Artemisia  vulgaris  heteiophylla 


HALL  AND  CLEMENTS 


Riilli  J.   Poieell  M. 


Artemisia  vulgaris  gnaphalodes.  f.g.  1 .       Artemisia  vulgaris  wrighti,  figs.  2  to  9.  Artemisia  bigelovi,  figs.  10  to  V, 


.   -r^SW^. 


Ruth  J.  PmceU  del. 


Artemisia  annua,  figs.  I  to  9. 


AiU-niisia  klotzschiana.  (igs.  10  to  18.  Artemisia  biennis,  figs.  19  to  28. 


HALL  AND  CLEMENTS 


Artemisia  ai)sintliiiiin.  figs.  1  U 


Vrtemisia  frigida,  figs.  9  to  18. 


HALL  AND  CLEMENTS 


Kidh  J.  Pmnll  M. 


Artemisia  pattersoni,  fig.  1.  Artemisia  scopulorum,  figs.  2  to  10. 


HALL  AND  CLEMENTS 


Ruth  J.   Pnwell  M. 


Artemisia  dracunculus  typica. 


HALL  AND  CLEMCNTS 


Hiilli  J.  r,m>u  ihl 


Artemisia  campestris  typica.  fig.  1.  Artemisia  campestris  pacifica,  figs.  2  to  11. 


HALL  AND  CLEMENTS 


Kuth  J.  Powell  del. 


Artemisia  campeslris  boreaiis.  figs.  1  to  4.  Artemisia  campestris  spithamaea,  fig.  5. 

Artemisia  campestris  pycnocephala,  figs.  6  to  12. 


HALL  AND  CLEMENTS 


Bulk  J.  Powell  , 


Artemisia  pedatifida,  figs.  1  to  10. 


Artemisia  (ilifolia,  figs.  11  to  18. 


HALL  AND  CLEMENTS 


^'■" '  0  -  - 

y'AV  ^  V 

/     ^    V    ^      ,'    V 

,   ■    '  y       \ 

/><:>.  ^.^~M^ 

i         "  ;  , "   t.  . . 

^7^':, 

~^           -'     ^     ^"    ;    ^ 

\^  ■  ':')• 

-^,    ^  '  .    -"^    ■     '     t 

\  ( '^  1 

.--S, 

*"'"''    ,-    --  ^^ 

--   ^  ^  .    'X'  -. 

7    "'-U-.  \  :  :< 

-/---. 

^''  -    / 

^   -f:^^' 

"^i>V 

^^^^'i  -' , 

'\' ' 

#£^^5V; 

/^n^v 

\  ^  ^  \     -  a''  ,    ^  ^ 

^  u  ~ 

8 

/  "'"-c- 

Rulh  J.   Powell  del. 

Artemisia  spinescens. 


HALL  AND  CLEMENTS 


Kuth  J.  Puwell  lid. 


Artemisia  t.identata  typica.  figs.  1  to  8.  Artemisia  tridentata  parishi,  figs.  9  to  11. 


HALL  AND  CLEMENTS 


Huth  J.  PmKtt  del. 

Artemisia  tridentata  Irifida,  figs.  1  and  2. 


Artemisia  tridentata  nova,  figs.  3  to  iO. 


HALL  AND  CLEMENTS 


Huth  J.  Powell  del. 

Artemisia  tridentata  arbuscula,  figs.  1  and  2. 


Artemisia  tridentata  rothrocki,  figs.  3  to  5. 


HALL  AND  CLEMENTS 


uth  J.   Powell  del. 


Artemisia  cana. 


HALL  AND  CLEMENTS 


Ruth   J.   Powell  tiel. 


Artemisia  rigida,  figs.  1  to  9.  Artemisia  py 


emaea,  figs.  10  to  17. 


HALL  AND  CLEMENTS 


Kuth  J.  Pou-dl  lid. 


Artemisia  palmeri. 


GENUS  CHRYSOTHAMNUS. 
HISTORY,  LIMITS,  AND  RELATIONSHIPS. 

The  genus  Chrysothamnus  is  a  member  of  the  Astereae  or  aster  tribe  of  the  Compositae 
and  is  closely  related  to  Haplopappus.  Within  the  limits  of  the  genus  as  here  set,  there 
have  been  described  a  total  of  88  forms,  nearly  all  of  which  have  been  given  the  rank  of 
species  at  one  time  or  another.  These  are  now  organized  into  4  sections,  12  species,  and 
40  subspecies.  Since  it  is  well  known  that  generic  lines  are  difficult  to  draw  in  this  group 
of  the  Compositae,  it  is  not  surprising  that  the  species  have  been  assigned  at  various  times 
to  no  fewer  than  6  different  genera.  Although  Chrysothamnus  was  proposed  by  Nuttall 
in  1840,  it  was  not  until  within  the  last  25  years  that  there  has  been  an  approximate 
agreement  among  systematists  as  to  its  proper  limits.  Even  at  the  present  day  there  is 
a  strong  tendency  to  unite  the  section  Punctati  of  this  treatise  with  Ericameria,  a  section 
or  subgenus  of  Haplopappus.  On  the  other  hand,  however,  in  only  three  instances  have 
species  of  other  genera  been  referred  to  this  one,  and  there  is  little  doubt  that  the  group  as 
now  accepted  is  a  natural  one. 

The  first  species  of  Chrysothamnus  to  receive  recognition  were  described  by  Pursh  as 
members  of  the  South  African  Chrysocoma  (Pursh,  Fl.  Am.  Sept.  2:517,  1814),  a  genus 
well  separated  from  the  one  now  under  consideration  by  its  nearly  globose,  solitary  heads, 
the  bracts  of  which  are  foliaceous  and  not  at  all  vertically  ranked,  and  by  its  compressed 
achenes.  This  usage  was  followed  by  Nuttall  four  years  later  in  his  Genera  of  North 
American  Plants,  where  two  species  are  described.  In  1834  Hooker  (Fl.  Bor.  Am.  2:24) 
described  a  species  under  the  name  Crinitaria  viscidifiora,  but  the  true  Crinitarias  are 
species  of  Aster  and  were  so  accepted  by  Bentham  and  Hooker  in  their  Genera  Plantarum 
(2:274,  1873),  in  which  work  viscidifiora  is  referred  to  Chrysothamnus  (p.  256). 

It  was  in  1836  that  DeCandolle  established  for  these  plants  a  name  under  which  they 
were  destined  to  be  known  more  or  less  continuously  for  over  half  a  century.  This  was 
Bigelovia  (DeCandolle,  Prodr.  5:329,  1836),  a  name  which,  as  Greene  has  pointed  out, 
had  at  least  five  chances  to  revert  because  of  its  having  been  previously  used  for  other 
genera,  and  what  is  still  worse,  a  name  that  was  made  to  include  species  so  widely  sepa- 
rated phylogenetically  that  it  can  not  possibly  be  retained  for  all  of  them.  Fortunately 
for  Chrysothamnus,  DeCandolle  took  as  the  type  of  his  Bigelovia  not  one  of  the  West 
American  shrubs  now  under  consideration,  but  the  decidedly  herbaceous  southeastern 
B.  nudata,  or  Chondrophora  nudata  as  it  is  sometimes  known.  The  true  Bigelovias  as 
represented  by  nudata,  differ  from  all  species  of  Chrysothamnus  not  only  in  their  very 
different  habit,  but  also  in  a  number  of  other  characters,  which  may  be  contrasted  as 
follows : 


Bigelovia  (Chondrophora). 
Perennial  herbs. 
Leaves  chiefly  basal,  the  few  upper  ones  different  in 

shape  from  the  lower. 
Involucral  bracts  spirally  imbricated,  with  no  tendency 

to  form  vertical  rows. 

Flowers  3  or  4. 

Receptacle  with  central  cusp. 

Corolla-lobes  very  long,  strongly  recurved. 

Achenes  short,  turbinate. 

Style-branch  abruptly  narrowed  to  the  appendage. 


Chrysothamnus. 
Shrubs. 
Leaves  equitably  distributed,  all  ahke. 

Involucral  bracts  imbricated  in  vertical  rows,  or  at 
least  with  an  obvious  tendency  towards  a  vertical 
alignment. 

Flowers  5  to  20  (occasionally  only  4). 

Receptacle  without  cusp. 

Corolla-lobes  shorter,  seldom  much  recurved. 

Achenes  longer,  narrower. 

Style  branch  tapering  to  the  appendage. 


Every  attempt  should  be  made  to  conserve  genera  and  generic  limits  after  they  have 
been  in  use  for  long  periods  of  time.  It  would  therefore  seem  desirable  to  use  Bigelovia 
in  a  sense  so  inclusive  as  to  embrace  both  of  the  above  groups.     This,  however,  would 


158  GENUS   CHRYSOTHAMNUS. 

convey  an  erroneous  idea  as  to  their  relationships,  for  it  is  quite  certain  that  the  true 
Bigelovias  and  the  Chrysothamni  are  not  descendants  of  the  same  immediate  stock  and 
that  in  each  case  there  are  more  closely  related  genera  to  be  considered.  Some  of  these, 
such  as  Petradoria,  for  example,  may  indeed  come  squarely  between  the  two.  The  only 
possible  connection  between  Bigelovia  and  Chrysoihamnus  seems  to  lie  in  the  only  half- 
shrubby  C.  graviineus.  In  addition  to  differing  from  Bigelovia  in  nearly  all  of  the  char- 
acters just  enumerated,  this  species  has  exceptionally  long  achenes  even  for  a  Chrysotham- 
nus.  If  connected  with  the  former  genus  at  all,  the  relation  would  need  to  be  sought 
through  Petradoria.  Although  Bigelovia  was  in  use  for  more  than  50  years,  and  even  to 
the  pre?cnt  is  occasionally  so  used  as  to  include  Chrysoihamnus,  the  limits  set  for  the  genus 
have  been  constantly  moved  about.  Thus  Gray,  in  1873,  enlarged  it  to  include  the  sec- 
tion Haplodiscus  (Proc.  Am.  Acad.  8:638),  a  section  now  belonging  to  Haplopappus 
section  Isocoma,  and  in  1884  the  same  authority  still  further  extended  the  boundaries  to 
include  a  portion  of  what  now  passes  as  Haplopappus  section  Ericameria  (Gray,  Syn.  Fl. 
P:141,  1884).  This  final  extension  left,  as  the  only  mark  of  distinction  between  Haplo- 
pappus and  Bigelovia,  the  presence  of  ray-flowers  in  the  former  and  their  absence  in  the 
latter.  This  was  obviously  an  artificial  separation,  as  is  evidenced  by  certain  species, 
such  as  H.  monactis,  H.  arborescens,  etc.,  in  which  the  ray-flowers  are  either  present  or 
abt^ent  even  on  the  same  plant.  What  now  seems  to  be  a  more  logical  arrangement  is 
given  farther  on,  the  only  object  in  mentioning  these  matters  here  being  to  call  atten- 
tion to  the  diverse  conception  of  the  limits  set  at  various  times  for  Bigelovia. 

Chrysoihamnus  was  established  as  a  genus  by  Nuttall  in  1840  (Trans.  Am.  Phil.  Soc. 
II,  7:323)  with  C.  pumilus  as  the  type  species.  Chronologically  it  therefore  follows 
De  Candolle's  Bigelovia  by  four  years.  This  in  turn  was  succeeded  two  years  later  by 
Torrey  and  Gray's  Flora,  in  which  Bigelovia  was  restricted  to  the  genuine  herbaceous 
species,  while  the  species  of  Chrysoihamnus  were  referred  to  Linosyris,  a  genus  previously 
considered  as  belonging  only  to  the  Old  World.  This  usage  was  continued  by  Gray  in 
the  Botany  of  the  Mexican  Boundary  Survey,  by  D.  C.  Eaton  in  the  Botany  of  the  King 
Expedition,  and  in  a  few  other  papers,  until  it  was  pointed  out  by  Bentham  and  Hooker 
(Genera  Plantarum  2:255,  274,  1873)  that  Chrysoihamnus  was  not  of  close  affinity  with 
true  Linosyris,  the  latter  being  better  considered  as  a  part  of  Aster.  The  former  was  thus 
reestablished  as  a  genus  and  extended  to  include  the  earlier  Bigelovia  of  De  Candolle. 
Gray  readily  accepted  this  arrangement  (Proc.  Am.  Acad.  8:637,  1873),  except  that  he 
asserted  the  priority  of  the  name  Bigelovia,  under  which  he  renamed  all  of  the  species. 
Bigelovia  then  came  into  general  use.  It  was  adopted  by  Bentham  and  Hooker  (Genera 
Plantarum  2:536,  1876)  and  was  used  by  Gray  in  the  Synoptical  Flora  and  elsewhere. 

It  thus  transpired  that  between  the  spurious  claims  of  Linosyris  on  the  one  hand  and 
of  Bigelovia  on  the  other,  the  generic  name  Chrysoihamnus  received  but  scant  attention 
until  it  was  revived  by  Greene  in  1895  (Erythea  3:92).  Not  only  did  Greene  point  out 
the  dubious  status  of  the  name  Bigelovia,  but  he  stoutly  defended  Nuttall's  segregation 
of  Chrysoihamnus  from  the  herbaceous  species  which  De  Candolle  took  as  the  type  of 
that  genus,  without,  however,  hitting  upon  some  of  the  more  important  distinctions  as 
above  set  forth.  Greene's  conception  of  the  genus  was  adopted  by  Nelson  in  his  paper, 
"Some  Rocky  Mountain  Chrysothamni"  (Bot.  Gaz.  28:369  to  377,  1899),  and,  with 
some  slight  modifications,  by  nearly  all  of  the  writers  of  recent  manuals  in  which,  how- 
ever, the  number  of  recognized  species  has  been  steadily  increasing.  It  is  also  the  con- 
cept adopted  in  the  present  paper,  except  that  C.  bloomeri  (Gray)  Greene  is  now  referred 
to  Haplopappus  and  that  two  species  here  included  were  assigned  to  Ericameria  by 
Greene.  It  was  characteristic  of  this  author  that,  although  he  possessed  a  keen  sense  of 
natural  grouping,  he  seldom  defined  groups  with  any  degree  of  precision.  In  the  present 
instance  no  generic  diagnosis  was  given  and,  aside  from  the  comparison  with  Chondro- 


HISTORY,   LIMITS,    AND   RELATIONSHIPS.  159 

phora  and  a  few  incidental  remarks,  no  discussion  of  relationships  was  entered  into  and 
no  differences  were  pointed  out  between  Chrysothamnus  and  the  several  species  of  Haplo- 
pappus,  with  which  it  seems  to  come  into  very  close  phylogenetic  connection. 

While  the  relation  of  Chrysothamnus  to  Bigelovia  has  received  much  attention,  its  pos- 
sible connection  with  Haplopappus  has  been  scarcely  more  than  suggested,  and  this 
mostly  through  the  transfer  of  species  from  one  to  the  other  genus  without  critical  com- 
ment. This  is  unfortunate,  for  the  origin  of  the  one  has  presumably  been  through  the 
other,  that  is,  Haplopappus  probably  includes  the  nearest  representatives  of  the  ancestral 
type  of  Chrysothamnus.  Indeed,  the  two  are  so  close  at  some  points  that,  if  it  were  not 
for  the  almost  universal  recognition  of  the  latter  during  the  last  twenty-five  years  under 
one  name  or  another,  their  complete  union  into  one  genus  might  be  seriously  considered. 
It  seems  unwise,  however,  to  disturb  generic  lines  as  long  as  the  present  arrangement 
does  no  violence  to  the  facts.  Any  other  course  would  open  the  way  for  innumerable 
generic  combinations  and  segregations,  each  based  upon  individual  judgment. 

Although  the  two  genera  now  under  consideration  closely  approach  each  other  in  some 
respects,  there  is  nevertheless  a  good  basis,  in  addition  to  usage,  for  recognizing  them 
as  distinct.  Chrysothamnus  differs  from  all  species  of  Haplopappus  in  its  consistently 
narrower  heads  and,  what  is  of  greater  importance,  a  decided  tendency  of  the  bracts  of 
the  involucre  to  fall  into  vertical  rows.  The  difference  between  this  arrangement  of  the 
bracts  and  the  regularly  imbricate  arrangement  encountered  in  the  latter  genus  is  per- 
haps comparable  to  the  difference  between  opposite  and  alternate  leaves,  but  the  bracts 
are  the  modified  leaves  of  a  highly  specialized  structure,  the  involucre,  and  hence  any 
variation  in  their  relative  positions  is  of  profound  significance.  In  some  species,  such  as 
C.  pulchellus,  the  vertical  rows  are  very  distinct,  in  others,  especially  among  the  Parryani, 
the  alignment  is  sometimes  quite  obscure.  It  is  believed,  however,  that  this  is  of  signifi- 
cance as  indicating  an  ancestral  trait,  even  when  there  is  scarcely  more  than  the  tend- 
ency left.  In  fact,  it  would  be  quite  remarkable  if  the  sharp  vertical  arrangement  should 
be  strictly  adhered  to  in  any  group  of  forms  as  large  as  this,  when  the  various  influences 
that  affect  growth  and  development  are  taken  into  account.  Another  distinguishing 
character,  doubtless  associated  with  the  vertical  arrangement  of  the  bracts,  is  the 
usually  well-developed  keel  of  these  structures.  In  the  more  typical  species  the  bracts 
are  rather  sharply  folded  longitudinally  along  the  midrib,  which  is  thus  emphasized  to 
form  a  distinctly  sharp  edge  or  keel.  This  is  most  noticeable  in  those  species  in  which 
the  vertical  rows  are  also  plainly  marked,  while  it  may  be  quite  obscure  when  the  rows 
themselves  are  not  easily  made  out. 

Chrysothamnus  is  thus  seen  to  differ  from  Haplopappus,  its  nearest  relative,  in  the 
narrow,  cylindraceous  heads,  in  the  vertical  arrangement  of  the  involucral  bracts,  and 
in  the  more  strongly  developed  midrib  of  these  bracts.  However,  in  all  of  these  char- 
acters there  is  a  shading-off  in  certain  species,  so  that  the  two  genera  are  not  sharply 
defined  from  each  other.  The  contact  between  them  is  perhaps  closest  through  the  sec- 
tion Ericameria  of  Haplopappus,  of  which  certain  members,  such  as  H.  brachylepis  and 
Ericameria  diffusa,  approach  species  of  Chrysothamnus  section  Punctati  very  closely. 
These  two  groups  meet  in  their  geographic  distribution,  possess  a  similar  habit,  and  in 
both  cases  the  foliage  is  marked  with  impressed  resin-dots.  This  easily  determined  pres- 
ence of  resin-dots  has,  in  fact,  led  to  the  union  of  the  Punctati  with  Ericameria  (that  is, 
with  Haplopappus  section  Ericameria)  in  most  accounts,  but  this  strictly  vegetative 
character,  which  has  probably  been  independently  developed  in  the  two  groups  and  is 
associated  with  their  xerophytic  habitat,  can  not  be  considered  as  of  importance  when 
compared  with  the  shape  of  the  heads  and  the  shape  and  arrangement  of  the  involu- 
cral bracts,  by  which  characters  the  Punctati  are  plainly  to  be  associated  with  Chryso- 
thamnus.    This  section  is  closely  related  also  through  C.  alhidus,  which,  although  of 


160  GENUS   CHRYSOTHAMNUS. 

another  section  and  universally  admitted  as  a  Chrysoihamnus,  has  resin-dots  almost  as 
prominent  as  those  of  the  Punctati  (compare  enlarged  leaves  of  plates  24  and  28,  and 
fig.  24). 

A  different  point  of  contact  between  the  two  genera  under  consideration  was  sug- 
gested by  Gray  (Proc.  Am.  Acad.  8:641,  1873)  and  the  suggestion  was  followed  up  by 
Greene  (Erythea  3:114,  1895).  According  to  these  authorities,  there  is  scarcely  any 
difference  between  Chrysoihamnus  holanderi  and  Haplopappus  discoideus.  It  must  be 
admitted  that  the  superficial  similarity  is  very  marked  and  that  the  peculiar  dense 
tomentum  of  the  twigs  is  suggestive  of  a  genetic  affinity.  But  the  heads  of  the  former 
are  much  narrower  than  those  of  the  latter,  the  involucre  is  decidedly  narrowed  at  the 
base,  and  the  bracts  are  carinate  and  positively  arranged  in  vertical  rows,  although 
these  rows  are  somewhat  obscure.  In  the  Haplopappus  the  bracts  are  much  more  folia- 
ceous,  flatter,  wider,  more  loosely  arranged,  not  carinate,  and  with  not  even  a  suggestion 


a 

Fig.  24. — Leaves  of  Chrysothamnua  teretifoli 

of  a  vertical  arrangement.  It  seems  that  here  again  we  have,  not  a  case  of  close  phylo- 
genetic  relationship,  but  rather  one  of  superficial  resemblance  between  plastic  groups 
that  have  come  under  the  same  environmental  influence.  It  seems  quite  likely  that 
the  two  botanists  whose  opinion  has  just  been  stated,  were  misled  through  errors  in 
identification.  At  the  National  Herbarium,  where  Greene  did  his  work,  there  are  only 
three  sheets  labeled  C.  holanderi  and  two  of  these  are  plainly  Haplopappus  discoideus. 
The  same  error  occurs  in  the  Greene  Herbarium  and  certain  early  determinations  at  the 
Gray  Herbarium  were  similarly  erroneous. 

Chrysoihamnus  is  thus  seen  to  be  a  fairly  homogeneous  assemblage  of  species;  to  be 
most  closely  related  to  Haplopappus  section  Ericameria  (or  possibly  section  Macro- 
nema) ;  and  to  bear  a  less  direct  relation  to  Chondrophora,  this  latter  consisting  of  the 
typical  species  of  De  Candolle's  Bigelovia. 

DIVISION  INTO  SECTIONS. 

The  first  attempt  at  an  arrangement  of  the  species  into  natural  sections  was  by  Gray 
in  1873  (Proc.  Am.  Acad.  8:638).  This  was  under  the  generic  name  of  Bigelovia,  which 
was  then  so  extended  as  to  include  many  species  since  referred  elsewhere.  Those  be- 
longing to  what  now  constitutes  the  genus  Chrysoihamnus  were  embraced  in  two  sections, 
namely,  Chrysolhamnopsis,  including  three  species,  all  of  which  now  form  part  of  C. 
parryi,  and  Chrysoihamnus,  composed  of  8  species  belonging  to  the  sections  Pundali, 
Typici,  Pulchelli,  and  Nauseosi  of  the  present  treatise.  The  primary  division  under 
this  second  section  was  based  chiefly  upon  the  pubescence  of  the  achenes,  a  character 


DIVISION    INTO  SECTIONS.  161 

SO  untrustworthy  as  to  render  the  arrangement  decidedly  artificial.  With  the  constant 
increase  in  the  number  of  species  and  of  our  knowledge  concerning  them,  Gray's  two 
sections  have  become  less  and  less  satisfactory.  Since  the  proposed  sectional  names 
are  not  applicable  under  Chrysothamnus,  an  entirely  new  classification  was  advanced  by 
Hall  in  1919  (Univ.  Calif.  Publ.  Bot.  7:160).  According  to  this  latest  arrangement, 
the  numerous  forms  are  assembled  into  five  natural  groups,  each  of  which  is  given  a 
formal  section  name.  Four  of  these  sections  are  adopted  in  the  present  paper,  the 
fifth,  or  Parryani,  being  now  united  with  the  Nauseosi,  and  the  sequence  is  modified  to 
bring  the  more  primitive  sections  at  the  beginning  of  the  list.  They  are  defined  as 
follows : 

Section  1.  Punctati.  Herbage  resinous-punctate,  the  dots  plainly  showing  as  defi- 
nite depressions;  twigs  brittle,  glabrous,  the  bark  at  first  green  but  soon  changing  to 
brown;  leaves  terete;  heads  in  open  panicles;  bracts  of  the  involucre  in  vertical  rows 
which  are  fairly  well  defined,  moderately  keeled,  obtuse  and  pointless,  chartaceous, 
either  with  or  without  an  obscurely  thickened  greenish  subapical  spot;  flowers  5  to  7; 
style-appendage  either  shorter  or  longer  than  the  stigmatic  portion;  achenes  slightly 
angled;  densely  pubescent.     Species:  teretifolius,  paniculatus. 

Section  2.  Typici.  Herbage  not  resinous-punctate  (somewhat  punctate  in  one 
species);  twigs  brittle,  glabrous  or  only  puberulent,  the  bark  usually  white;  leaves  ob- 
lanceolate  to  narrowly  linear  but  not  terete;  heads  in  rounded  or  flat-topped  cymes,  or 
solitary  and  subracemose  only  in  C.  gramineus;  bracts  of  the  involucre  in  poorly  defined 
vertical  rows,  not  strongly  keeled,  obtuse  to  acuminate  but  none  continued  into  slender 
herbaceous  tips,  more  or  less  chartaceous,  not  rarely  some  of  the  outer  with  firmer  and 
indistinctly  greenish  apex;  flowers  5  to  7;  style-appendage  either  shorter  than  or  much 
exceeding  the  stigmatic  portion;  achenes  slightly  angled,  pubescent  or  in  two  species 
glabrous  and  10-striate.     Species:   albidus,  greenei,  gramineus,  vaseyi,  viscidiflorus. 

Section  3.  Pulchelli.  Herbage  not  resinous-punctate;  twigs  brittle,  glabrous  or 
puberulent,  the  bark  greenish-white;  leaves  oblanceolate  to  revolute  filiform;  heads  in 
rounded  cymes;  bracts  of  the  involucre  in  very  sharply  defined  vertical  ranks,  strongly 
keeled,  attenuate  but  never  to  an  herbaceous  tip,  firmly  chartaceous  throughout;  flowers 
about  5;  style-appendage  shorter  than  or  only  slightly  exceeding  the  stigmatic  portion; 
achenes  nearly  prismatic,  not  striate,  glabrous  or  nearly  so.  Species:  pulchellus,  de- 
pressus. 

Section  4.  Nauseosi.  Herbage  not  resinous-punctate;  twigs  flexible,  densely 
covered  with  a  pannose  tomentum,  this  more  or  less  infiltrated  with  a  resinous  sub- 
stance; leaves  lanceolate  or  oblanceolate  to  linear-filiform  but  never  truly  terete,  some- 
times reduced  to  scales;  heads  in  small  panicles,  racemes,  or  spikes  or  reduced  to  flat- 
topped,  rounded,  or  more  elongated  cymes  or  thyrses;  bracts  of  the  involucre  in  fairly 
well  defined  vertical  ranks,  or  these  obscure,  moderately  to  strongly  keeled,  obtuse  to 
acute,  never  with  greenish  apex  but  prolonged  in  one  species  into  a  slender  tip,  thin- 
chartaceous  throughout;  flowers  usually  5  to  15  but  sometimes  as  many  as  20;  style- 
appendage  very  slender  and  long  exserted,  nearly  equaling  or  exceeding  the  stigmatic 
portion;  achenes  slightly  angled,  pubescent  or  glabrous,  not  striate.  Species:  pyrami- 
datus,  parryi,  nauseosus. 


162 


GENUS   CHRYSOTHAMNUS. 


Fio.  25. — Phylogenetic  chart  of  the  sections  and  species  of  Chryaothamntu. 


ORIGIN   AND    DEVELOPMENT   OF   THE    SECTIONS.  163 

ORIGIN  AND  DEVELOPMENT  OF  THE  SECTIONS. 

The  relationships  between  the  various  species  will  be  taken  up  in  detail  in  connection 
with  the  descriptive  accounts  of  each,  as  will  also  the  relationships  between  the  sub- 
species. However,  it  seems  desirable  here  to  sketch  the  lines  of  evolutionary  develop- 
ment, at  least  as  far  as  this  concerns  the  principal  species  and  the  sections,  and  to  present 
the  results  in  diagrammatic  form.  Although  the  general  laws  of  phylogeny,  as  far  as 
they  are  understood,  form  the  basis  of  this  discussion,  it  does  not  follow  that  the  results 
represent  more  than  the  probable  relationships.  It  is  believed,  however,  that  this 
attempt  to  throw  the  species  into  natural  evolutionary  groups  will  be  of  service,  espe- 
cially if  the  doubtful  cases  are  not  definitely  placed  until  more  is  known  concerning  them. 

It  has  been  shown  that  the  contact  of  Chrysothamnus  with  its  most  closely  related 
genus,  that  is,  Haplopappus,  is  apparently  best  represented  by  the  Punctati.  This  does 
not  necessitate  the  assumption  that  the  other  sections  have  arisen  through  this  one. 
Such  a  hypothesis  would  lead  to  the  conclusion  that  the  character  of  impressed-punctate 
foliage  was  once  developed  and  then  lost.  While  this  is  possible,  it  seems  improbable. 
More  logical  is  the  assumption  that  the  Chrysothamnus  stock  was  developed  from  an 
ancestral  group  close  to  Haplopappus  section  Ericameria  but  without  the  resin-dots  of 
that  group.  The  development  first  concerned  itself  with  modifications  of  the  involucre 
until  this  structure,  or  rather  this  assemblage  of  structures,  was  different  from  anything 
in  Ericameria,  especially  in  its  subcylindric  shape  and  in  the  arrangement  of  the  bracts. 
It  was  perhaps  from  such  a  group  that  the  Punctati  were  derived,  their  vegetative  changes, 
especially  the  formation  of  resin-dots,  paralleling  to  some  extent  those  going  on  in  Eri- 
cameria. In  some  such  manner  were  these  two  sections  evolved,  sections  so  alike  in 
superficial  appearance  as  often  to  be  confused  with  each  other,  yet  so  unlike  in  origin, 
indicated  by  difference  in  fundamental  characters,  as  now  to  be  assigned  to  different 
genera.  This  is  apparently  a  case  of  parallel  variation  in  two  groups  not  widely  sepa- 
rated phylogenetically.  The  connection  with  Ericameria  is  best  seen  by  comparing 
Chrysothamnus  paniculatus  with  Ericameria  diffusa.  The  Punctati  are  only  two  in 
number,  both  shrubs  of  the  Southwest  and  very  closely  related  to  each  other. 

Without  running  counter  to  the  laws  of  phylogeny,  it  may  next  be  assumed  that  the 
hypothetical  group  already  mentioned  gave  rise  somewhat  farther  up  to  the  Typici.  It 
seems  reasonable  that  this  section  is  more  primitive  than  any  of  the  three  remaining 
ones,  in  view  of  the  fact  that  each  of  these  exhibits  some  striking  peculiarity  not  pos- 
sessed by  the  Typici  and  indicative  in  each  case  of  a  higher  order  of  development.  Tak- 
ing then  the  Typici  as  the  central  section,  we  find  its  most  characteristic  representative 
to  be  C.  viscidiflorus.  This  is  a  very  widely  distributed  species,  which  has  itself  under- 
gone modifications  in  several  directions,  as  is  indicated  by  the  nine  subspecies  and  numer- 
ous forms  discussed  in  detail  farther  on.  But  aside  from  its  success  as  a  biologic  type,  it 
possesses  no  characters  indicative  of  an  extreme  evolutionary  development.  The  in- 
volucre gives  positive  evidence  of  vertical  rows  in  the  arrangement  of  its  bracts,  but  these 
rows  are  not  very  sharply  defined;  the  twigs  are  devoid  of  any  highly  specialized  pubes- 
cence; and  neither  bracts  nor  style-appendages  are  unusually  elongated.  It  has  a  very 
intimate  relative  in  C.  greenei,  but  the  other  three  members  of  the  section,  gramineus, 
vaseyi,  and  alhidus,  are  less  closely  connected. 

The  Pulchelli  are  so  much  like  the  Typici  that  there  can  be  no  doubt  as  to  their  close 
phylogenetic  origin.  The  habit,  the  nature  of  the  wood  and  bark,  the  type  of  inflores- 
cence, and  the  relative  length  of  appendage  and  stigmatic  portion  of  the  style-branch 
are  almost  identical.  But  in  the  Pulchelli  the  carination  of  the  bracts  and  their  vertical 
arrangement  is  carried  to  an  extreme  not  otherwise  known  in  the  genus,  and  the  long, 
glabrous  but  not  striate  achenes  are  very  different  from  those  of  the  Typici.  The  two 
species  comprising  this  section  are  very  closely  related  to  each  other. 


164  GENUS   CHRYSOTHAMNUS. 

In  order  to  reach  the  Nauseosi  it  is  now  necessary  to  leave  the  line  which  culminates 
in  the  highly  modified  PulcheUi  and  pick  up  the  evolutionary  thread  somewhere  below 
the  Typici.  This  is  necessitated  by  the  appearance  in  the  Nauseosi  of  a  seemingly  super- 
ficial but  really  very  important  character,  namely,  the  remarkably  pannose  tomentum 
of  the  twigs.  To  one  familiar  with  this  matted,  felt-like  covering  so  closely  applied  to  the 
bark,  it  represents  a  character  of  greater  importance  than  is  usually  found  in  the  pubes- 
cence. Since  this  indicates  an  evolutionary  stage  not  reached  by  the  PulcheUi,  and  since  . 
these  on  the  other  hand  present  highly  specialized  characters  not  found  in  the  Nauseosi, 
the  conclusion  follows  that  neither  has  been  derived  from  the  other.  The  latter  is  there- 
fore indicated  as  branching  off  from  near  the  Typici.  It  includes  C.  pyramidalus,  a  little- 
known  Mexican  species  which  separated  from  the  original  stock  in  early  times,  and  two 
others  which  are  much  better  known.  These  are  C.  parryi,  a  polymorphous  species  with 
its  center  of  distribution  in  the  Great  Basin,  and  C.  nauseosus,  an  abundant  and  widely 
distributed  species  of  western  North  America.  Ten  subspecies  of  the  former  and  20  of 
the  latter  are  recognized  in  the  present  treatment. 

CRITERIA  FOR  RECOGNITION  OF  SPECIES  AND  SURSPECIES. 

Achene. — Two  very  unlike  types  of  achene  are  encountered  in  the  genus,  but  it  is  easy 
to  see  how  one  of  these  may  have  been  derived  from  the  other.  In  the  common  form  it 
is  either  obscurely  5-angled  or  terete  and  5-nerved,  always  tapering  slightly  from  summit 
to  base  but  not  sufficiently  so  to  be  described  as  turbinate,  and  usually  covered  with  a 
dense  pubescence.  In  the  other  form,  which  occurs  only  in  C.  vaseyi  and  C.  gramineus, 
the  essentially  glabrous  achene  is  nearly  terete  or  slightly  flattened,  tapers  but  slightly 
toward  the  base,  and  is  distinctly  10-striate.  This  type  is  so  different  from  the  extreme 
of  the  other  that  the  character  might  be  considered  as  generic  were  it  not  for  other  fea- 
tures, especially  of  vaseyi,  which  definitely  relate  these  species  to  the  other  Chrysothamni. 
The  two  are  not  so  far  apart  as  would  at  first  seem,  as  is  indicated  by  such  achenes  as 
those  of  C.  nauseosus  leiospermus,  which  are  glabrous,  terete,  and  with  5  principal  striae, 
but  often  with  an  additional  fainter  nerve  between  each  pair  of  the  more  prominent  ones, 
thus  approaching  the  terete,  10-nerved  type  of  C.  gramineus.  The  pubescence,  or  its 
absence,  has  been  used  as  a  specific  character,  even  in  cases  where  the  achenes  are  other- 
wise identical  with  those  of  other  species.  But  it  has  been  shown  in  a  recent  paper  (Hall 
in  Univ.  Calif.  Publ.  Bot.  7:173,  1919)  that  this  character  is  a  variable  one  and  that 
three  species  based  largely  upon  it,  bigelovi,  glareosus,  and  leiospermus,  are  all  subspecies 
of  C.  nauseosus.  In  C.  pulchellus  the  achenes  are  usually  glabrous,  but  sometimes  spar- 
ingly pubescent.  Although  this  variation  has  been  noted  in  descriptions  (for  example, 
Rydberg,  Fl.  Rocky  Mts.  855,  1917),  there  has  been  no  attempt  to  use  it  as  a  basis  for  a 
new  species.  A  tendency  toward  the  loss  of  the  character  in  a  species  in  which  the 
achenes  are  almost  always  densely  villous  or  strigose  is  seen  in  C.  viscidiflorus,  where  a 
form  described  as  C.  marianus  Rydberg  has  achenes  only  sparsely  strigose  or  at  times 
apparently  almost  glabrous.  The  length  is  a  valuable  feature,  but  one  to  be  used  with 
caution,  since  in  most  herbarium  specimens  the  achenes  are  not  fully  developed. 

Pappus. — The  pappus  is  so  nearly  uniform  in  Chrysothaynnus  that  it  has  not  proved 
very  helpful  in  supplying  distinctions  between  species  or  subspecies.  It  is  more  rigid 
in  some  than  in  others.  Sometimes  it  changes  more  rapidly  and  decidedly  with  age  to  a 
tawny  hue  or  becomes  ferruginous,  but  while  such  characters  are  of  assistance,  even 
when  variable,  they  are  impossible  of  expression  in  quantitative  terms  and  therefore 
difficult  of  application.  The  length  of  the  pappus  is  of  more  definite  value,  especially 
when  taken  in  comparison  with  the  length  of  the  corolla. 

Style-branches. — In  Chrysothamnus  and  related  genera  much  significance  has  been 
attached  to  the  shape  and  length  of  the  style-branch  and  its  appendage.     While  these 


CRITERIA.  165 

structures  undoubtedly  furnish  characters  of  much  taxonomic  value,  it  is  unfortunate  that 
their  descriptions  have  been  based  upon  superficial  examinations,  usually  with  the  aid 
only  of  a  hand-lens  and  not  upon  exact  measurements.  This  applies  particularly  to 
statements  of  relative  length  of  appendage  and  stigmatic  portion.  The  tabulation  of  a 
large  series  of  measurements  now  indicates  that  the  ratio  between  appendage  and  stig- 
matic portion  is  far  from  constant  for  any  one  species  or  perhaps  even  for  any  one  sub- 
species. It  also  indicates,  however,  that  the  ratio  is  much  higher  for  some  species  than 
for  others.  Pairs  of  species  can  be  selected  in  which  no  overlapping  of  ratios  occurs, 
so  that  the  character  can  there  be  used  to  advantage.  But  any  attempt  to  apply  the 
ratio  throughout  the  genus  as  a  never-failing  specific  character  would  result  in  a  cleavage 
running  counter  to  all  other  features  and  it  would  therefore  lead  to  an  unnatural  arrange- 
ment of  the  forms. 

The  extent  of  variation  within  a  single  large  species  is  indicated  in  table  23  (p.  230).  The 
ratio  is  of  further  significance  when  used  to  indicate  tendencies  in  the  various  sections. 
In  the  Punctati  the  stigmatic  portion  and  the  appendage  are  approximately  equal  in 
length,  sometimes  one  being  the  longer  and  sometimes  the  other.  Among  the  Typici 
the  otherwise  anomalous  C.  albidus  has  unusually  long  appendages,  while  in  the  other 
three  the  appendage  is  uniformly  shorter  than  the  stigmatic  portion  or  only  slightly 
exceeds  it  in  occasional  specimens  of  vaseyi.  A  similar  condition  holds  in  the  Pulchelli, 
indicating  as  do  other  features  that  these  two  sections  are  very  close  phylogenetically. 
In  the  Nauseosi,  the  appendage  is  always  well  developed  and  usually  but  not  always 
longer  than  the  stigmatic  portion.  In  two  subspecies  of  nauseosus  it  is  regularly  shorter 
and  in  a  third  it  is  sometimes  so.  The  shape  is  often  given  in  descriptions,  but,  aside 
from  the  difficulty  of  expressing  this  accurately,  it  possesses  little  value.  Long  append- 
ages are  naturally  more  slender  than  short  ones  and  they  are  usually  more  attenuate. 
The  so-called  "broad  appendages"  of  certain  species  are  perhaps  not  broader  by  measure- 
ment than  others,  but  are  only  seemingly  so  because  of  their  shortness. 

Stamens. — The  stamens  have  thus  far  furnished  characters  of  diagnostic  value  in  only 
one  instance.  The  tips  are  acute  in  all  species  except  C.  albidus,  but  in  this  they  are 
obtuse  and  also  decidedly  shorter  than  in  the  others  (except  the  small-flowered  pyra- 
midatus).  It  is  possible  that  detailed  studies  might  reveal  further  stamen  differences 
of  value,  but  a  preliminary  survey  indicates  that  the  prospects  are  not  promising. 

Corolla. — The  shape  of  the  corolla  is  always  tubular-funnelform,  although  there  is 
some  variation  between  the  species.  In  some  the  throat  enlarges  more  abruptly  than 
in  others,  but  the  line  of  demarkation  between  tube  and  throat  is  so  indefinite  that  the 
differences  can  not  be  expressed  in  quantitative  terms.  Since  also  the  shape  depends 
upon  the  age  and  condition  of  the  specimen,  whether  fresh,  dry,  or  boiled,  such  expres- 
sions as  "abruptly  expanding"  or  "slenderly  tapering"  are  only  relative  and  of  sUght 
value.  The  total  length  of  the  corolla  is  a  character  of  greater  significance.  While 
this  fluctuates  to  disappointing  extremes  in  some  of  the  polymorphous  species,  in  certain 
other  cases  it  is  sufficiently  constant  to  be  of  use  and  should  always  be  included  in  de- 
scriptions of  new  forms.  Thus,  in  the  Punctati  the  corolla  always  measures  between  6 
and  6.5  mm.  long,  whereas  in  C.  nauseosus  it  measures  6.2  to  12  mm.  and  in  C.  parryi 
8  to  12  mm.  The  character  is  especially  useful  in  distinguishing  the  two  species  of  the 
Pulchelli,  the  corolla  in  one  measuring  7  to  9.0  mm.,  in  the  other  10  to  14  mm.  How- 
ever, when  the  whole  series  of  species  in  the  genus  is  considered,  it  is  found  that  the 
overlapping  between  them  is  so  frequent  and  the  range  of  variation  is  so  great  in  certain 
cases  (more  than  50  per  cent  of  the  length  in  C.  viscidifiorus)  that  the  utilization  of  this 
criterion  in  keys  is  very  limited.  Even  in  applying  it  as  a  measure  of  the  extent  of 
differentiation  where  only  two  species  are  concerned,  it  must  be  used  only  after  a  con- 
siderable number  of  flowers  from  different  plants  have  been  measured.     The  total 


166 


GENUS   CHRYSOTHAMNUS. 


lengths  as  well  as  the  extent  of  variation  for  each  of  the  major  species  is  given  in  table 
17,  while  tables  22  and  23  (p.  207  and  p.  230)  give  similar  data  for  the  more  common 
forms  of  two  of  the  larger  species. 

The  depth  to  which  the  corolla-limb  is  cleft,  that  is,  the  length  of  the  corolla-lobe, 
has  been  used  as  a  diagnostic  character  for  many  proposed  species.  The  actual  length, 
however,  has  never  been  given  (except  in  a  recent  paper  by  one  of  the  present  authors) 
and  the  relative  length,  if  mentioned  at  all,  is  stated  in  terms  so  general  as  to  indicate 
that  measurements  have  not  been  made.  When  a  large  series  of  specimens  are  meas- 
ured, it  is  found  that  the  absolute  length  of  the  lobe  as  well  as  the  ratio  between  lobe- 
length  and  corolla-length  usually  exhibits  considerable  variation  within  a  single  species. 
The  exceptions  are  C.  paniculaius  and  C.  teretifolius,  both  non-plastic  species  in  which 
the  lobes  are  constantly  near  1  mm.  in  length,  and  C.  albidus,  in  which  they  have  the 
remarkable  length  of  2  to  2.5  mm.  Even  within  the  "small  species"  of  some  botanists, 
that  is,  the  subspecies  of  the  present  treatment,  the  range  of  variation  in  the  length  of 
the  lobe  is  too  great  to  permit  of  rigid  application.  It  is  very  useful,  however,  as  indi- 
cating certain  tendencies  and  can  sometimes  be  correlated  with  other  characters  and 
with  geographic  distribution.     This  is  especially  noticeable  in  the  case  of  three  close 

Table  17. — Length  of  corolla  and  of  corolla-lobes  in  the  species  of  Chrysothamnus. 


No.  of 
collections 
measured. 


Length  of 

including 
lobes. 


Length  of 
coroUa- 
lobes. 


Ratio  of 

lobe-length 

to  total 

length. 


Punctati : 

C.  paniculatus. 

C.  teretifolius. . 
Typici: 

C.  gramineus . . 

C.  vaseyi 

C.  viscidiflorus. 

C.  greenei 

C.  albidus 

Pulchelli: 

C.  pulchellus.  .  , 

C.  depressus. . . , 
Nauseosi: 

C.  pyramidatus 

C.  parryi 

C.  nauseosus.  .  . 


e.Oto  6.2 

6.0  6.5 

12.0 

6.6  6.5 

4.5  7.0 

4.0  4.5 

7.0  8.0 


0.8  to  1.2 
1.0       1.2 


per  cent. 
13  to  18 


per  ceni. 
15.4 
16.7 


21 
7       25 
6.5  32 


'  Computed  by  taking  the  average  of  all  of  the  individual  ratios. 

subspecies  of  C.  nauseosus  included  in  table  23  (p.  232).  These  are  pinifoHus,  of  Colorado 
and  adjacent  States,  with  lobes  which  average  only  0.9  mm.  long  (0.7  to  1.3  mm.); 
consimilis,  which  has  its  center  of  distribution  in  Nevada  and  in  which  the  lobes  average 
1.3  mm.  long  (1  to  1.6  mm.);  and  viridulus,  of  eastern  California,  in  which  the  lobes 
average  2.0  mm.  long  (1.7  to  2.5  mm.).  These  three  subspecies,  all  inhabitants  of 
alkaline  soils,  differ  only  in  the  lobe-lengths  and  in  a  few  minor  tendencies,  robustness, 
inflorescence,  etc.,  which  can  be  correlated  only  partially  with  this.  The  overlapping 
in  the  lobe-length  occurs  most  frequently  in  specimens  from  localities  where  the  ranges 
meet,  so  that  some  individuals  can  not  be  definitely  placed.  This  variation  with  geo- 
graphic distribution  is  paralleled  in  certain  other  characters  and  is  representative  of  a 
tendency  of  frequent  occurrence,  namely,  that  within  a  given  series  of  forms  the  greatest 
floral  development  is  among  those  of  westerly  or  southwesterly  distribution.  Thus,  in 
C.  nauseosus  the  maximum  and  also  the  highest  average  length  of  both  involucre  and 
corolla  are  reached  in  the  subspecies  mohavensis  and  bernardinus  of  the  Southwest  (see 
table  23).      Similarly  within  the  subspecies  spedosus  it  is  found  that  specimens  from 


CRITERIA,  167 

western  Nevada  and  northwestern  California  have  generally  longer  involucres  and 
corollas  than  those  from  farther  east. 

The  position  taken  by  the  corolla-lobe  is  of  some  interest.  Long  lobes  are  inclined 
to  spread  or  even  to  recurve;  short  lobes  are  usually  erect  and  in  some  cases  are  connivent 
around  the  stamen-tube.  Such  extremes  are  sometimes  found  within  a  single  species, 
as  in  C.  nauseosus  viridulus  and  C.  n.  gnaphalodes. 

The  pubescence  of  the  corolla  exhibits  some  striking  variations,  without  offering  any- 
thing of  more  than  subspecific  value.  The  tube  is  either  glabrous  or  minutely  puberu- 
lent,  even  in  plants  belonging  to  the  same  variety.  Quite  different  is  the  additional  long 
arachnoid  pubescence  that  appears  on  the  tube  of  some  subspecies  of  nauseosus.  This 
consists  of  loose,  crooked  hairs  often  1.5  mm.  long.  Such  pubescence  would  be  of  much 
diagnostic  value  were  it  constant  and  if  it  did  not  occur  in  varying  amounts.  Among 
specimens  referred  to  a  broad-leaved  form  of  subspecies  speciosus  of  this  species,  some 
have  abundantly  arachnoid-pubescent  corolla-tubes  (Hall  10853,  Heller  7192),  while 
others  are  almost  identical  with  these  in  all  respects,  except  that  the  tube  has  only  the 
usual  crisp  pubescence  common  throughout  the  genus  (Univ.  Calif.  Herb.,  87248,  31163). 
Similarly  among  fairly  uniform  collections  of  subspecies  typicus,  the  tube  is  found  to  be 
either  essentially  glabrous  (Howell  Lakes,  Wyoming,  Nelson  5315),  or  short-hirsute 
(Laramie,  Wyoming,  July  29,  1889  Greene),  or  more  rarely  arachnoid-pubescent 
(Laramie,  Wyoming,  Nelson  2787).  In  subspecies  hololeucus  the  long  hairs  are  usually 
very  conspicuous.  However,  among  apparently  identical  plants  growing  within  a  few 
meters  of  one  another,  some  will  be  found  to  have  a  copious  pubescence,  others  a  scant 
amount,  others  none  at  all  (Benton,  California,  Hall  10654).  In  other  collections  of 
hololeucus  the  long  hairs  will  be  only  2  or  3  in  number  {Hall  10610)  or  entirely  wanting 
on  plants  a  few  kilometers  removed.  The  tips  of  the  corolla-lobes  are  sometimes  con- 
spicuously long-hairy.  This  character  is  constant  for  C.  parryi  latior  as  far  as  indi- 
cated by  the  few  collections  at  hand.  In  C.  nauseosus  it  constantly  occurs  only  in 
subspecies  turhinatus  and  junceus.  In  the  latter  it  is  of  but  little  value,  for  the  hairs 
are  few  in  number  and  deciduous.  The  lobes  of  C.  nauseosus  bigelovi  are  usually  glab- 
rous, but  in  one  collection  they  vary  from  sparsely  to  copiously  villous  {Hall  III40  UC). 
In  the  Mexican  C.  pyramidatus  the  lobes  are  puberulent  at  the  tip.  It  seems,  there- 
fore, that  the  pubescence  of  the  corolla-parts  furnishes  criteria  of  doubtful  specific 
value,  but  of  some  use  in  the  segregation  of  minor  forms  and  as  a  clue  in  tracing  the 
lines  of  evolution. 

Number  of  flowers  in  the  head. — Aside  from  C.  parryi  and  C.  pyramidatus  the  number 
of  flowers  is  almost  constantly  5.  As  one  would  expect,  this  number  occasionally  drops 
to  4,  or  more  often  it  increases  to  6  or  7.  In  C.  parryi,  however,  the  heads  have  more 
numerous  flowers,  and  here  the  character  is  of  some  importance  for  recognition  of  sub- 
species. In  fact,  it  has  been  heretofore  considered  specific  as  between  parryi  and  howardi, 
but  the  series  of  counts  enumerated  in  table  22  indicates  very  clearly  that  it  can  not  be 
used  for  this  purpose,  especially  when  the  other  subspecies  are  taken  into  account. 

Involucre. — In  common  with  most  other  Compositae,  the  involucre  of  Chrysothamnus 
ofTers  characters  of  considerable  importance.  The  bracts  are  arranged  in  5  more  or  less 
evident  vertical  rows.  When  these  ranks  are  well  defined  the  involucre  is  sharply  5- 
angled;  when  they  are  obscure  it  is  more  rounded  and  without  definite  angles.  The 
number  of  bracts  in  each  row  varies  from  3  to  5,  there  being  a  tendency  in  each  species 
toward  either  the  smallest  or  the  highest  number  but  with  no  absolute  fixity.  Such  char- 
acters as  these  are  of  much  service  in  arriving  at  conclusions  as  to  specific  or  sectional 
limits  when  a  large  series  of  specimens  are  at  hand  for  comparison,  but  being  relative 
they  are  difficult  of  application  when  one  is  making  determinations  from  keys  and 
descriptions.     The  shape  of  the  scales  themselves  is  also  of  value.     It  is  more  or  less  cor- 


168  GENUS    CHRYSOTHAMNUS. 

related  with  their  arrangement  in  vertical  rows.  When  the  rows  are  obscure  the  bracts 
are  likely  to  be  flattish,  without  a  distinct  keel,  and  usually  obtuse  unless  appendaged; 
when  the  rows  are  well-defined  the  bracts  are  folded  or  at  least  incurved  from  the  midrib, 
which  thus  forms  a  sort  of  keel,  and  the  bract  is  more  or  less  boat-shaped  and  usually  acute. 
The  former  is  characteristic  of  most  of  the  Typici,  while  the  latter  is  best  seen  in  C.  nau- 
seosus  and  especially  in  the  Pulchelli. 

The  texture  of  the  bract  escapes  every  attempt  at  its  characterization,  except  when 
herbaceous  tips  or  thickenings  appear.  A  definite  herbaceous  tip,  or  appendage,  is 
present  only  in  C.  parryi,  where  it  is  common  for  some  of  the  outer  bracts  to  be  drawn 
out  at  the  apex  into  a  slender  greenish  appendage.  While  this  is  useful  as  a  specific 
character  when  considered  as  a  tendency,  it  can  not  be  applied  as  a  constant  one.  Cer- 
tain specimens  referable  here  by  all  other  characters  have  the  tip  poorly  developed  or 
entirely  wanting  in  some  heads.  The  herbaceous  thickening  referred  to  is  even  less  reli- 
able than  the  prolonged  apex.  It  is  usually  found  as  a  minute  rounded  mark  and  is 
subapical.  In  using  this  character  it  must  be  borne  in  mind  that  except  in  one  species 
the  spot  is  distinctly  green  only  in  fresh  material.  In  dried  specimens  it  fades  to  a  dull 
brown.  It  has  been  used  as  a  specific  trait  in  the  segregation  of  at  least  four  proposed 
species.  In  C.  teretifolius  and  C.  vaseyi  it  is  connected  with  other  and  more  im- 
portant characteristics  which  it  supplements  very  well.  In  teretifolius  especially,  the 
decidedly  thickened  spot  is  noticeably  green,  even  in  herbarium  specimens.  Quite  differ- 
ent is  the  case  of  elegans.  This  is  so  close  to  certain  other  forms  that  the  presence  of 
the  subapical  spot,  which  is  here  never  sharply  defined  and  often  very  obscure  or  even 
wanting,  can  not  save  it  from  reduction  to  subordinate  rank  under  C.  viscidiflorus.  Like- 
wise in  the  fourth  case,  namely  linifoHus,  a  reduction  to  a  subspecies  of  viscidiflorus  is 
necessitated  by  the  discovery  of  intermediate  forms. 

The  size  of  the  involucre  and  the  number  of  its  bracts  have  been  investigated  as  to 
their  value  as  differentiating  criteria.  The  breadth  of  the  head  is  a  poor  character,  since 
it  depends  largely  upon  the  state  of  maturity  and  the  manner  of  taking  the  measurement. 
Furthermore,  it  varies  somewhat  with  the  number  of  flowers.  The  height  is  more  defi- 
nite and  can  sometimes  be  used  to  advantage,  but  only  in  dealing  with  very  unlike  species 
or  when  only  subspecific  distinctions  are  looked  for.  When  a  large  series  of  measurements 
is  taken,  these  are  found  to  present  an  annoying  range  of  variation,  sometimes  even 
within  a  single  taxonomic  subspecies.  This  is  indicated  for  the  subspecies  of  C.  parryi 
in  table  22  (p.  207).  A  similar  tabulation  but  with  less  difference  between  the  extremes 
could  be  presented  for  the  subspecies  of  C.  viscidiflorus.  The  most  that  can  be  said  of 
the  results  of  such  studies  of  these  two  species  is  that  there  is  a  tendency  toward  either 
short  or  long  involucres  in  certain  subspecies,  but  that  the  overlapping  is  too  pronounced 
to  warrant  the  use  of  this  criterion  for  specific  segregation.  Somewhat  different  is  the 
case  of  C.  nauseosus,  as  will  be  seen  by  reference  to  table  23  (p.  230).  In  this  species  the 
involucre  has  the  remarkable  range  in  length  of  from  6  to  12  mm.  Furthermore,  pairs  of 
subspecies  can  be  selected  in  which  there  is  no  overlapping,  for  example,  gnaphalodes 
with  an  involucre  length  of  6  to  8.2  mm.  and  bernardinus  with  one  of  10  to  12  mm.  While 
this  would  furnish  a  specific  character  as  between  these  two  forms,  its  use  for  that  pur- 
pose must  be  abandoned  because  of  other  subspecies  which  form  intergrading  series 
between  them;  for  example,  those  in  which  the  length  runs  6.5  to  8  mm.,  6  to  9  mm., 
7.5  to  10  mm.,  and  10  to  12  mm.,  respectively.  Furthermore,  the  remarkable  variation 
exhibited  within  certain  subspecies,  as  brought  out  in  the  table,  is  a  warning  to  proceed 
cautiously  in  the  use  of  this  character.  When  the  bracts  are  in  sharply  defined  vertical 
rows  the  total  number  usually  varies  by  fives.  This  necessarily  follows  from  the  fact 
that  there  are  five  rows  and  that  in  any  particular  head  the  number  of  bracts  in  any  one 
row  is  the  same  as  in  any  other.     But  since  the  number  of  bracts  per  row  varies  within 


every  species,  there  is  an  overlapping  in  the  totals,  so  that  this  character  again  possesses 
no  specific  value.  It  is  useful,  however,  in  distinguishing  divisions  of  those  species  in 
which  the  alinement  of  the  rows  has  been  lost  and  where  in  consequence  the  total  varies 
by  units  rather  than  by  fives.  This  is  brought  out  in  table  22  (p.  207),  where,  for  example, 
it  will  be  noted  that  the  number  for  the  asper-vulcanicus-monocephalus  group  of  subspecies 
of  C.  parryi  runs  from  8  to  13,  with  an  average  of  10.4,  whereas  in  the  howardi-attenuatus- 
nevadensis  group  it  runs  from  11  to  21,  with  an  average  of  about  13. 

Inflorescence. — The  heads  are  borne  in  cymes,  racemes,  spikes,  or  panicles.  The  cyme 
is  by  far  the  most  common  type  and  occurs  with  some  modifications  almost  throughout 
the  Typici  and  Pulchelli  and  in  C.  nauseosus.  In  the  anomalous  C.  gramineus  the 
inflorescence  is  apparently  a  much  reduced  raceme,  while  the  racemose  type  is  char- 
acteristic for  C.  parryi.  In  this  last,  however,  the  peduncles  are  sometimes  so  branched 
that  small  panicles  are  the  result.  This  condition  gives  an  inflorescence  simulating 
the  compound  cymes  sometimes  seen  in  C.  nauseosus.  In  the  Punctati  the  inflorescence 
is  essentially  spicate  in  one  species,  truly  paniculate  in  the  other.  Observations  in  the 
field  have  demonstrated  that  the  size  and  density  of  the  inflorescence  are  too  variable  to 
be  of  much  taxonomic  significance.  Although  conspicuous  in  their  extremes,  the  forms 
resulting  from  such  considerations  can  not  be  satisfactorily  treated  even  as  subspecies. 

Leaves. — The  leaves  are  always  alternate  (partly  fascicled  in  one  species)  and  entire. 
The  remaining  characters,  such  as  size,  shape,  and  texture,  are  seldom  of  diagnostic  value 
as  far  as  species  are  concerned.  Terete  leaves  occur  only  in  the  Punctati;  in  one  species 
(gramineus)  they  are  exceptionally  wide  and  without  intraspecific  gradations;  and  in 
one  other  case  the  shape  is  useful  as  a  specific  distinction  (between  pulchellus  and  depres- 
sus),  but  these  leaf-characters  are  always  used  in  connection  with  others  and  aside 
from  the  instances  here  mentioned,  the  foliage  furnishes  criteria  useful  only  when  dealing 
with  subspecies.  A  consistent  attempt  has  been  made  to  utilize  the  number  of  nerves 
and  their  prominence,  but  without  much  success.  It  is  only  in  comparing  species  which 
are  rather  clearly  separated  on  other  characters  that  such  features  can  be  called  into  use 
and  then  only  as  additional  evidence.  Much  has  been  made  heretofore  of  the  number  of 
veins  as  a  specific  character  in  segregations  from  C.  viscidifiorus,  but  here  the  number 
depends  largely  upon  the  width  of  the  leaf.  There  is  one  plain  midvein  and  usually  two 
others  that  start  from  the  base  but  are  soon  lost  or  become  invisible.  Very  often  a  plant 
will  seem  to  have  only  1-veined  leaves,  but  on  close  examination  a  few  leaves  with  2  or 
3  veins  wUl  be  found  (for  example,  C.  parryi  monocephalus,  Univ.  Calif.  Herb.  76001; 
C.  parryi  nevadensis,  Univ.  Calif.  Herb.  31167;  C.  viscidifiorus  typicus,  Univ.  Calif. 
Herb.    51644,    203178). 

Stem  and  hark. — To  one  accustomed  to  handling  the  plants  in  the  field,  there  is  a 
decided  difference  in  the  stems  of  certain  species,  although  the  characters  are  not  easily 
described.  Thus,  in  the  Typici,  Pulchelli,  and  Punctati  the  twigs  are  very  brittle,  whereas 
in  the  Nauseosi  they  are  much  more  flexible.  The  bark  of  the  year-old  twigs  is  usually 
white  in  the  Pulchelli  and  Typici,  green  or  brownish,  although  sometimes  covered  with  a 
white  pubescence,  in  the  Nauseosi.  The  striation  of  the  younger  stems  is  often  of  diag- 
nostic value.  In  the  last-mentioned  section,  however,  this  is  likely  to  depend  upon  the 
nature  of  the  hairy  covering,  which  may  be  either  loose,  thus  masking  the  striae,  or 
closely  compacted  and  thus  exposing  them.  The  older  bark  of  the  main  trunks  affords 
specific  characters,  but  not  of  such  a  nature  as  to  be  usable  in  keys.  The  color  of  the 
plant  as  a  whole,  whether  due  to  bark,  foliage,  or  only  pubescence,  has  been  made  use  of 
in  specific  descriptions,  but  this  is  too  variable  and  elusive  to  be  of  value  in  dealing  with 
any  category  above  that  of  subspecies. 

Roots.— It  is  quite  probable  that  specific  distinctions  could  be  derived  from  the  system 
of  root-branching  if  this  were  well  understood.     The  only  root  studies  made  were  in  the 


170  GENUS   CHRYSOTHAMNUS. 

two  species  that  are  the  most  polymorphous  in  other  regards,  namely,  viscidiflorus  and 
nauseosus.  A  considerable  number  of  each  of  these,  several  hundred  in  all,  were  examined 
in  the  field.  The  difference  between  the  species  was  very  marked.  In  all  of  the  five  sub- 
species examined  of  the  former,  the  main  root  divides  near  the  surface  of  the  soil,  the 
branches  spreading  out  at  a  moderate  depth  and  influenced  in  their  direction  by  the 
nature  of  the  stony  soil  in  which  the  plants  grow.  In  the  ten  subspecies  examined  of 
nauseosus,  the  root  usually  continues  downward  to  a  considerable  depth  as  a  well-defined 
tap-root,  emitting  only  secondary  lateral  rootlets.  This  species  grows  in  better  and 
deeper  soil  than  viscidiflorus.  Along  the  edges  of  its  habitat,  where  the  soil  is  often  shal- 
lower or  quite  stony,  the  root  habit  may  simulate  that  of  viscidiflorus,  but  it  is  believed 
that  the  two  types  are  different  in  their  origin.  A  striking  peculiarity  of  the  root  is 
common  in  C.  nauseosus  hololeucus.  In  this  form,  which  inhabits  dry  sandy  stream-ways 
and  fans,  the  large  root  is  often  twisted  upon  itself  and  easily  breaks  up  into  strands  like 
those  of  a  rope.  The  cause  of  this  is  not  known,  but  it  is  suggested  that  such  roots  are 
really  composite  and  have  been  formed  by  the  intertwining  of  the  single  roots  of  several 
plants.  At  any  rate,  such  a  possibility  must  be  taken  into  account  when  making  studies 
in  individual  variation. 

Pubescence. — Two  very  distinct  types  of  pubescence  are  encountered.  Although  char- 
acters of  the  pubescence  are  generally  untrustworthy  and  are  easily  modified  by  changes 
in  the  environment,  in  this  genus  the  two  types  are  so  unlike,  the  absence  of  intergrading 
stages  is  so  marked,  and  their  appearance  runs  so  nearly  parallel  with  other  characters, 
that  pubescence  furnishes  a  safe  guide  even  for  sectional  distinctions.  This  applies, 
however,  only  to  the  presence  or  absence  of  a  peculiar  pannose  tomentum.  The  number 
and  the  distribution  of  ordinary  hairs  furnish  criteria  as  unreliable  here  as  elsewhere. 

The  pannose  tomentum  referred  to  occurs  in  all  of  the  Nauseosi  but  nowhere  else  in  the 
genus.  It  consists  of  a  dense  coating  of  long,  weak  hairs,  which  have  become  more  or 
less  infiltrated  with  a  resinous  exudation  from  the  twigs.  The  inner  portion  of  this 
mass  closely  invests  the  twigs  like  a  tight-fitting  coat.  The  outer  ends  of  the  trichomes 
may  be  either  loose,  thus  presenting  a  light,  fluffy  appearance,  or  they  may  be  closely 
impressed  with  the  inner  layers.  In  the  latter  case,  the  surface  is  often  so  smooth  that 
the  woolly  layer  is  mistaken  for  the  bark  itself,  until  it  is  scraped  up  by  a  knife-edge  or 
scalpel.  This  has  led  even  careful  botanists  wrongly  to  describe  certain  forms  as  glabrous 
or  nearly  so  and  thus  to  mask  their  true  relationships.  For  example.  Gray  described 
the  branchlets  of  Linosyris  bigelovi  as  with  scarcely  a  perceptible  pubescence;  the  same 
author  gives  "greenish  and  minutely  canescent"  for  the  branches  of  Bigelovia  juncea, 
earlier  described  by  Greene  as  cinereous ;  Greene  has  described  the  twigs  of  C.  pinifolius, 
C.  virens,  C.  laetevirens,  and  others  as  glabrous  or  nearly  so;  Nuttall,  in  characterizing 
C.  speciosus,  made  no  mention  of  the  pubescence  of  the  stem,  but  at  the  same  place  he 
proposed  a  variety  albicaulis  based  only  upon  the  dense  and  white  tomentum  of  the  stems 
and  suggested  that  it  might  be  a  distinct  species.  The  types  of  all  of  these  have  been 
examined  and  found  to  have  twigs  clothed  with  a  dense  felt-like  tomentum.  For  this 
and  for  other  reasons  they  are  now  classified  as  subspecies  of  C.  nauseosus. 

Aside  from  its  presence  or  absence,  the  tomentum  does  not  afford  specific  characters. 
Its  duration,  amount,  color,  and  extent  are  all  too  variable  to  indicate  more  than  varietal 
or  subspecific  rank.  It  is  certain,  however,  that  some  of  these  qualities  are  heritable,  at 
least  for  a  few  generations.  Certain  subspecies  of  C.  nauseosus,  differing  among  them- 
selves in  the  color  and  extent  of  the  tomentum,  come  "true  to  seed"  in  these  respects 
when  grown  under  uniform  conditions  in  the  Botanical  Garden  of  the  University  of  Cali- 
fornia. The  same  holds  for  transplants  made  by  transferring  the  roots  of  these  sub- 
species. While  only  extremes  were  used  in  these  experiments,  all  intermediate  forms  are 
found  in  the  field  (although  not  always  in  the  same  locality),  so  that  such  characters  are 
difficult  to  apply  in  the  identification  of  described  groups. 


CRITERIA.  171 

Pubescence  in  Chrysothamnus,  aside  from  the  special  type  of  tomentum  just  described, 
is  scarcely  noticeable,  the  twigs  and  foliage  being  never  more  than  puberulent.  In  the 
Punctati  and  in  certain  species  of  other  sections,  it  is  entirely  wanting.  Sometimes,  as 
among  the  subspecies  of  viscidiflorus,  it  will  occur  as  a  fairly  dense  though  minute  puberu- 
lence  in  certain  plants,  while  others  almost  exactly  duplicating  these  in  every  other  respect 
will  be  perfectly  glabrous.  This  is  so  frequent  that  glabrous  and  puberulent  forms  may 
be  expected  of  any  variad  in  that  species.  Their  possible  origin  through  mutation  is 
suggested  in  discussing  the  relationships  of  C.  viscidiflorus.  When  such  forms  are  quite 
marked  and  of  frequent  occurrence,  and  especially  if  they  have  been  given  specific  rank 
elsewhere,  they  are  treated  in  this  paper  as  subspecies ;  when  they  appear  only  occasion- 
ally, they  are  mentioned  only  in  the  list  of  minor  variations.  To  assign  specific  or  even 
subspecific  rank  in  all  such  cases  would  so  enlarge  and  complicate  taxonomic  monographs 
that  their  usefulness  would  be  seriously  impaired.  It  is  very  evident,  however,  that  a 
complete  systematic  treatment  will  need  to  take  account  of  all  such  variations. 

Resins,  oils,  and  other  physiological  products. — Throughout  the  genus  there  is  a  notable 
tendency  to  the  formation  of  resins  and  oils.  This  is  associated  with  the  xerophytic 
habitat  of  the  plants.  The  resins  are  not  exuded  through  the  trichomes,  but  directly 
through  the  surface  of  the  epidermis  proper.  The  herbage  is  therefore  often  glutinous 
or  viscid.  This  character  is  more  marked  in  some  species  than  in  others  without,  how- 
ever, furnishing  a  useful  criterion  for  distinguishing  them.  The  reason  is  that  the  differ- 
ence is  entirely  relative  and  dependent  quite  as  much  upon  local  conditions  or  even  time 
of  day  as  upon  an  inherent  quality.  Much  more  important  is  the  presence  of  definite 
pits,  or  wells,  into  which  the  resin  exudes,  forming  the  resin-dots  of  the  Punctati.  These 
are  structural  and  therefore  of  greater  significance  than  resinous  or  viscid  coatings. 
Since  they  are  easily  recognized  their  presence  furnishes  an  ideal  specific  character. 

The  odor  of  the  herbage  is  an  aid  to  one  familiar  with  the  plants.  Its  diagnostic  value 
is  not  great  because  of  the  absence  of  standards  for  comparison.  The  Punctati  possess 
a  peculiar  and  very  pleasing  odor  whereby  one  may  recognize  a  plant  as  belonging  to  this 
section,  even  though  the  flowers  are  wanting.  In  C.  nauseosus  the  odors,  probably  due 
to  the  presence  of  essential  oils,  vary  somewhat  in  unison  with  other  characters,  so  that 
they  are  useful  in  a  few  cases  for  the  recognition  of  subspecies.  Thus  the  subspecies 
triridulus  emits  a  very  strong,  disagreeable  odor  when  the  twigs  are  broken  or  when 
burned.  A  very  similar  though  less  pronounced  odor  is  noticeable  in  the  closely  related 
subspecies  consimilis,  pinif alius,  and  graveolens.  On  the  other  hand,  the  herbage  of  sub- 
species gnaphalodes,  and  especially  of  subspecies  hololeucus,  usually  has  an  exceedingly 
pleasant  fragrance,  "suggesting  a  combination  of  tropical  fruits  and  berries."  Under 
favorable  conditions  these  forms  may  be  recognized  by  the  odor  alone. 

Habit. — All  of  the  species  of  Chrysothamnus  are  shrubs.  In  one  case,  namely  C.  gram- 
ineus,  tlie  shrubby  nature  is  not  pronounced,  although  the  base  of  the  stem  is  perennial 
and  decidedly  woody.  In  other  species  the  plants  are  sometimes  quite  short,  but  they 
are  always  woody  and  partake  of  the  habit  of  shrubs;  plainly  they  are  reduced  or  dwarf 
forms  closely  related  to  the  more  shrubby  types.  The  transition  between  these  dwarf 
shrubs,  some  of  which  are  only  1  dm.  high,  to  the  arborescent  forms,  which  sometimes 
attain  a  height  of  24  dm.,  is  so  gradual  as  to  preclude  the  use  of  this  character  for  dis- 
tinguishing categories  above  the  rank  of  subspecies. 


172  GENUS   CHRYSOTHAMNUS. 

FIXITY  OF  SPECIES  AND  SUBSPECIES  AND  OF  THEIR  CHARACTERS. 

The  best  evidence  regarding  the  fixity  of  forms  and  of  their  characters  is  obtained 
by  experimental  methods.  In  the  case  of  perennials  like  Chrysothamnus,  such  experi- 
ments must  necessarily  extend  over  a  long  period  of  years,  in  order  to  permit  of  the 
growth  of  several  generations  from  seed  of  known  origin.  Such  work  has  been  under- 
taken in  the  present  case,  but  results  are  now  available  from  only  the  first  generation. 
Transplants  of  rooted  specimens  of  a  few  of  the  forms  have  also  been  made  and  the 
resulting  changes  studied.  The  data  from  these  experiments  were  used  in  arriving  at 
the  opinions  here  expressed,  but  much  more  extensive  observations  were  made  upon  the 
wild  plants,  especially  as  to  the  extent  of  variation  under  different  ecologic  conditions 
and  in  various  geographic  areas.  Finally,  a  close  statistical  and  analytical  study  has 
been  made  of  series  of  specimens  brought  in  from  the  field  for  this  purpose.  As  a  result 
of  the  evidence  assembled  from  these  various  sources,  it  is  found  that  the  genus  includes 
a  few  species  in  which  the  characters  are  remarkably  constant,  species  which  are  hence 
known  to  be  non-plastic  and  which  do  not  break  up  into  minor  segregates.  But  it  is 
also  found  that  certain  other  species  are  in  a  highly  plastic  condition,  such  species 
comprising  a  large  number  of  closely  related  subspecies,  many  of  which  are  in  turn 
breaking  up  through  mutation  and  gradual  variation  into  innumerable  races  and  ecads. 
The  variability  of  the  characters  themselves  has  been  already  indicated  to  some  extent 
in  the  preceding  chapter  on  discussion  of  criteria. 

The  most  nearly  constant  of  the  species  are  those  which  are  assumed,  for  other 
reasons,  to  be  the  most  primitive ;  namely,  C.  paniculatus  and  C.  teretifolius.  These  two 
are  sharply  set  off  from  the  other  members  of  the  genus  and  do  not  intergrade  into 
each  other.  As  evidence  of  the  constancy  of  their  characters  may  be  cited  an  exami- 
nation of  11  specimens  of  teretifolius,  all  from  different  localities,  in  which  the  length 
of  the  corolla  did  not  vary  by  more  than  0.5  mm.,  the  length  of  the  lobes  by  only  0.2 
mm.,  and  the  ratio  of  lobe-length  to  corolla-length  by  3  per  cent.  As  contrasted  with 
this,  the  corolla  of  C.  nauseosus  varies  by  as  much  as  6  mm.  in  length,  the  lobes  by  2 
mm.,  and  the  ratio  by  over  27  per  cent.  This  suggests  that  nauseosus  is  a  composite 
species,  while  teretifolius  is  not.  But  even  within  a  well-defined  subspecies  of  the 
former,  for  example  graveolens,  the  corolla  varies  to  the  extent  of  2  mm.,  the  lobes  by 
0.7  mm.,  and  the  ratio  between  the  two  by  7.5  per  cent.  Similar  figures  have  been 
obtained  for  length  of  involucre,  relative  lengths  of  style-appendage  and  stigma,  and 
other  characters.  The  conclusion  is  therefore  inevitable  that  teretifolius  is  in  a  set 
condition  as  contrasted  with  the  highly  variable  and  composite  nauseosus. 

With  C.  teretifolius  (or  the  less  well-known  paniculatus)  as  the  species  with  characters 
the  most  definitely  fixed,  and  with  C.  nauseosus  as  the  one  which  is  the  most  plastic, 
the  others  exhibit  varying  degrees  of  mobility.  Three  of  them  are  so  local  in  their 
distribution,  at  least  as  far  as  present  collections  indicate,  that  they  can  not  be  defi- 
nitely assigned  as  to  variability,  but  all  of  them  will  doubtless  be  found  to  be  fairly 
constant  in  their  characters.  These  are  gramineus,  albidus,  and  pyramidatus.  C.  vaseyi 
is  also  well  fixed  in  its  characters,  there  being  no  varieties,  while  even  its  ecologic  forms 
are  few  and  not  well  marked.  C.  viscidijlorus  presents  a  very  different  case.  It  un- 
doubtedly represents  the  extreme  of  plasticity  among  the  Typici.  The  ten  subspecies 
here  described  represent  only  a  small  proportion  of  the  forms  known  in  the  field.  It 
seems  that  the  species  is  capable  of  occupying  areas  of  considerable  diversity,  and  this 
probably  accounts  for  its  wide  distribution.  The  large  number  of  habitats  occupied  is 
equaled  by  the  large  number  of  forms.  While  most  of  these  have  arisen  through  eco- 
logic factors  and  are  fluctuating  in  their  nature,  others  are  quite  certainly  more  deep- 
seated  in  their  origin.  This  is  indicated  by  the  absence  of  intergrading  forms.  The 
more  striking  of  these  are  given  subspecific  rank  in  the  present  paper.  It  is  believed 
that  none  of  them,  with  the  possible  exception  of  linifolius,  is  as  well  established  and 


FIXITY    OF   SPECIES   AND    SUBSPECIES.  173 

as  sharply  defined  from  its  neighbors  as  are  most  of  the  subspecies  of  C.  nauseosus 
or  of  C.  parryi.  Chrysothamnus  greenei  and  C.  pulchellus  both  are  somewhat  variable, 
as  is  indicated  by  their  subspecies.  However,  their  variations  are  chiefly  those  of  habit, 
foliage,  and  size  of  head  and  flowers,  and  therefore  perhaps  not  of  the  importance  that 
their  taxonomic  status  would  seem  to  indicate. 

Chrysothamnus  parryi,  as  here  extended,  comprises  an  extensive  series  of  variations. 
In  addition  to  the  ten  accepted  subspecies  there  are  a  number  of  other  forms,  some 
representing  combinations  of  minor  characters  while  others  are  intermediate  or  outlying 
forms  obviously  brought  about  by  unusual  environmental  conditions.  A  few  of  these 
are  described  under  the  heading  of  Minor  variations.  The  conclusion  is  that  C.  parryi  is 
in  a  highly  unstable  state. 

Table  18. — Variation  in  plants  of  Chrysothammis  nauseosus  grounng  under  apparently  uniform  conditions. 


Subspecies  graveolens: 

North  of  Fort  Collins,  Colo. : 

Plant   1 

2 

3 


Subspecies  speciosus: 
Near  Strevell,  Ida 

Plant   1 

2 

3 


Length, 

including 

lobes. 


9  8 
10.0 
10.0 
9.0 
9.0 


0  8 
0.5 
0.7 
0.7 
0.8 


Ratio  of 
lobe-length 


Per  cent. 
16.2 
13.7 
12.9 
14.7 
13.3 

16.7 
15.5 
12.6 
16.7 
13.9 
14.4 


Length  of 
Btigmatic 
portion. 


Length  of 
appendage. 


mm. 
1.5 
2.0 


Ratio  of 
appendage- 
length  to 

total 
length  of 
branch. 


Per  cent. 

66  7 
67.9 


67.1 
53.8 
60  6 
54.2 
57.1 


But,  as  already  indicated,  the  species  now  undergoing  the  greatest  amount  of  change, 
and  the  one  which  exhibits  the  greatest  variety  of  forms,  is  C.  nauseosus.  All  of  the  20 
subspecies  described  in  this  paper  are  presumably  more  than  ecologic  forms  and  it  is 
almost  certain  that  at  least  most  of  them  include  still  other  units  the  characters  of 
which  are  inherited.  Even  such  characters  as  the  amount  and  color  of  the  tomentum 
are  heritable,  as  indicated  by  plants  now  growing  in  the  Botanical  Garden  of  the  Uni- 
versity of  California.  In  these  plantings,  for  example,  the  very  white  herbage  of  sub- 
species hololeucus  stands  out  in  strong  contrast  to  the  gray  of  subspecies  gnaphalodes 
and  to  the  yellowish-green  of  subspecies  viridulus  and  hiospermus  in  neighboring  rows. 
On  the  other  hand,  the  distinctive  fragrance  of  certain  forms  seems  to  be  lost  when  these 
are  grown  in  the  coastal  districts.  Other  evidence  as  to  the  importance  of  minor  char- 
acters is  obtained  by  a  comparison  with  geographic  distribution.  While  a  few  subspecies 
extend  over  wide  areas,  most  of  them  have  a  definite  geographical  range  from  which  the 
most  closely  related  subspecies  are  excluded.  However,  such  pairs  often  meet  at  the 
borders  of  their  ranges,  and  here  they  seem  to  grade  insensibly  into  each  other.  Whether 
this  is  actually  the  case  or  the  intermediate  forms  are  the  result  of  hybridization  is  a 
question  that  will  require  a  genetic  analysis  for  its  answer.  The  most  remarkable 
mixing  of  two  subspecies  in  this  manner  which  has  been  thus  far  noted,  takes  place  at 


174  GENUS    CHRYSOTHAMNUS. 

Soda  Springs,  Esmeralda  County,  Nevada,  where  the  ranges  of  consimilis  and  viridulus 
meet.  Entirely  different  from  the  characters  just  considered  are  those  which  are  plainly 
modified  by  changes  in  the  environment.  These  have  to  do  with  habit,  size,  and  direc- 
tion of  leaf,  relative  amount  (but  not  nature)  of  pubescence,  leafiness,  size  of  inflores- 
cence, etc.  Such  characters  often  can  be  readily  accounted  for  when  the  habitat  is 
examined.  The  ecologic  origin  of  the  forms  is  further  suggested  by  their  occurrence  at 
numerous  localities  and  without  regard  to  geographic  isolation,  but  mutations  may  also 
occur  in  this  manner. 

The  extent  of  variation  in  one  floral  character  in  plants  of  a  single  subspecies  and 
apparently  of  uniform  germinal  constitution  is  indicated  in  table  18. 

The  figures  used  in  table  18  are  in  each  case  the  average  of  several  measurements. 
Similar  studies  of  specimens  at  other  localities  and  for  oiher  subspecies  indicate  an 
equally  great  variability.  The  conclusion  is  that  all  of  the  more  common  subspecies 
of  C.  nauseosus  are  in  a  highly  plastic  condition  and  that  there  exists  even  within  a  single 
colony  a  large  number  of  minor  forms.  Whether  this  is  due  to  the  presence  of  numerous 
genetic  strains  or  biotypes,  or  whether  it  is  the  result  of  fluctuating  variability  is  not 
within  the  province  of  this  paper  to  decide.  In  either  case,  it  indicates  that  "improve- 
ment" in  any  desired  direction  may  be  brought  about  by  selection,  or  by  hybridization, 
or  by  both  of  these  methods.  In  this  connection  it  may  be  pointed  out  that  the  percent- 
age content  of  rubber  in  subspecies  of  C.  nauseosus  varies  for  different  plants  in  a  single 
locality  in  much  the  same  manner  as  the  index  characters  used  in  the  above  table.  This 
is  shown  in  a  table  of  180  chemical  analyses  recently  reported  upon  by  Hall  and  Good- 
speed  (Univ.  Calif.  Publ.  Botany  7:227  to  233,  1919). 

GENERIC  DIAGNOSIS. 

CHRYSOTHAMNUS  Nuttall,  Trans.  Am.  Phil.  Soc.  11,  7:323,  1840. 

Branching  shrubs  and  half  shrubs.  Roots  fibrous,  either  with  or  without  a  taproot. 
Stems  erect  or  ascending,  never  twining.  Herbage  glabrous  to  tomentose,  commonly 
resinous  and  aromatic,  impressed-punctate  in  two  species.  Leaves  alternate,  with- 
out distinction  between  blade  and  petiole,  entire  or  only  scabro-serrulate.  Heads  in 
cymes,  thyrses,  spikes,  racemes,  or  panicles.  Involucre  cylindraceous ;  bracts  mostly 
carinate  or  with  a  strong  midrib,  well  imbricated  in  more  or  less  distinct  vertical  ranks, 
chartaceous  or  coriaceous,  only  the  tips  sometimes  herbaceous.  Ray-flowers  entirely 
wanting.  Disk-flowers  4  to  20.  Corolla  tubular-funnelform,  the  tube  passing  gradu- 
ally into  the  throat,  5-toothed  or  5-cleft.  Style-appendages  exserted  from  the  corolla- 
tube,  lanceolate-attenuate  to  filiform  or  subulate,  either  longer  or  moderately  shorter 
than  the  stigmatic  portion.  Achenes  slender,  terete  or  slightly  angled  or  flattened, 
rarely  striate,  glabrous  to  densely  pubescent.  Pappus  copious,  soft,  dull  white  to  reddish. 
(Bigelovia,  section  Spuriae  De  Candolle,  Prodr.  5:329,  1836.  Bigelovia,  sections  Chryso- 
thamnopsis  and  Chrysothamnus  Gray,  Proc.  Am.  Acad.  8:641,  642,  1873,  and  Syn.  Fl. 
12:136,    137,    1884.) 

According  to  Nuttall,  the  genus  was  named  Chrysothamnus  from  its  affinity  to  Chryso- 
coma  and  from  its  brilliant  golden-yellow  flowers.  A  literal  translation  is  "golden 
wood,"  or  "golden  bush."  The  latter  is  used  to  some  extent  in  the  Rocky  Mountain 
States  as  a  common  name  for  C.  nauseosus.  This  species  as  well  as  a  number  of  others  is 
more  commonly  called  rabbit-brush,  which  was  given  because  of  the  utilization  of  the 
thickets  by  rabbits  as  places  of  refuge.  They  sometimes  eat  the  young  shoots,  but  this 
is  not  a  universal  habit.  (For  a  discussion  of  common  and  Indian  names  see  Univ.  Calif. 
Publ.  Bot.  7:190,  1919.) 


C.    PANICULATUS.  175 

Key  to  the  Sections  and  Species  of  Chryaothamnua. 

Herbage  resinous-punctate;  leaves  terete  (Punctati). 

Bracts  all  pale,  without  greenish  spot 1.  C.  -panicuLcUus  (p.  175). 

Outer  bracts  with  a  distinct  greenish  subapical  spot 2.  C.  teretifolius  (p.  176). 

Herbage  not  resinous-punctate;  leaves  oblanceolate  to  narrowly  linear  or  nearly  terete. 
Twigs  glabrous  or  puberulent,  not  closely  tomentose. 

Bracts  moderately  keeled,  the  vertical  rows  not  sharply  defined;  achenes  either 
decidedly  pubescent  or  glabrous  and  l6-striate  (Typici). 
Achenes  glabrous  or  nearly  so  and  10-striate. 

Leaves  lanceolate,  5  to  10  mm.  wide,  strongly  3-  or  5-nerved;  corolla  12  mm. 

long;  '  style-appendages  twice  as  long  as  the  stigmatic  portion .  .     3.  C.  gramineua  (p.  178). 
Leaves  linear  or  very  narrowly  oblanceolate,   1  to  2  mm.  wide,   1-nerved; 
corolla  7  mm.  or  less  long;  style-appendages  scarcely  exceeding 

or  shorter  than  the  stigmatic  portion , 4.  C.  vaseyi  (p.  179). 

Achenes  densely  pubescent  or  rarely  sparsely  so,  but  never  striate. 

Involucral  bracts  obtuse  to  acute,  but  never  slenderly  acuminate 5.  C.  viscidiflorus  (p.  180). 

Involucral  bracts  (some  or  most  of  them)  slenderly  acuminate  or  with  an 
abrupt  mucro. 
Corolla  about  5  mm.  long,  yellow;  anther-tips  lanceolate,  very  acute,  about 

0.5  mm.  long 6.  C.  greenei  (p.  190). 

Corolla  7  to  8  mm.  long,  whitish;  anther-tips  ovate,  obtuse,  about  0.2  mm. 

long 7.  C.  albidiis  (p.  192). 

Bracts  strongly  keeled,  the  vertical  rows  very  distinct;  achenes  glabrous  or  only 
minutely  pubescent,  not  striate  (Pulchelli). 

Leaves  fiUform  to  Unear;  corolla  10  to  14  mm.  long 8.  C.  pulchellus  (p.  193). 

Leaves  spatulate  or  oblanceolate;  corolla  7  to  9  mm.  long 9.  C.  depressus  (p.  195). 

Twigs  covered  with  a  pannose  or  felt-like  tomentum,  this  sometimes  so  close  as  to 

escape  observation  (Nadseosi). 

Heads  in  leafy  spike-like  or  raceme-like  clusters,  these  sometimes  branching  to  form 

panicles;  outer  bracts  of  involucre   commonly   prolonged  into 

a  slender  herbaceous  tip  or  appendage  (e.xcept  in  C.  pyramidatus). 

Involucre  about  6  mm.  high;  upper  leaves  fascicled 10.  C.  pyramidatus  (p.  197). 

Involucre  10  to  15  mm.  high;  leaves  not  fascicled 11.  C.  parryi  (p.  198). 

Heads  cymose  at  the  ends  of  the  branches,  the  inflorescence  sometimes  compound 
and  elongated,  bracts  of  the  involucre  obtuse  to  acute,  the  outer 
ones  regularly  shortened  and  devoid  of  herbaceous  tip 12.  C.  natiseosus  (p.  209). 

Section  I.    PUNCTATI. 

1.  CHRYSOTHAMNUS  PANICULATUS  (Gray)  Hall,  Univ.  Calif.  Publ.  Bot.  3:58,  1907. 

Plate  24. 

Shrub  6  to  20  dm.  high,  with  several  or  numerous  main  stems  from  the  base,  forming 
a  broad,  rounded  plant;  bark  of  the  older  portions  dark  gray,  rough;  twigs  brittle, 
spreading,  leafy,  glabrous  but  resinous  and  viscid,  at  first  green  (or  with  a  gray  waxy 
bloom)  and  impressed-punctate,  later  turning  brown  and  striate;  leaves  terete,  shortly 
mucronate,  1  to  3  cm.  long  (much  shorter  in  the  inflorescence),  glabrous  but  very  resinous 
and  marked  by  numerous  impressed  resin-dots,  sometimes  with  a  gray  waxy  bloom; 
heads  in  profuse  terminal  panicles  or  the  inflorescence  occasionally  reduced  and  sub- 
racemose  but  never  spicate;  involucre  5  to  6  mm.  high;  bracts  13  to  17,  in  5  obvious  but 
not  sharply  defined  vertical  ranks,  oblong,  obtuse,  not  carinate,  rather  thin,  glabrous, 
stramineous,  without  apical  spot;  flowers  5  to  8;  corolla  tubular-funnelform,  the  tube 
passing  gradually  into  a  much  wider  throat,  about  6  mm.  long,  glabrous;  lobes  lance- 
ovate,  about  1  mm.  long,  nearly  erect,  glabrous;  anther-tips  linear,  acute,  0.5  mm. 
long;  style-branches  long-exserted,  the  appendage  varying  from  only  slightly  to  twice 
longer  than  the  stigmatic  portion;  achenes  tapering  from  summit  to  base,  5-angled, 
about  4  mm.  long  when  mature,  appressed- villous ;  pappus  scarcely  equaling  the  corolla, 
white.     {Bigelovia  paniculata  Gray,  Proc.  Am.  Acad.  8:644,  1873.) 

Arid  and  stony  slopes,  especially  in  dry  streamways,  from  southwestern  Utah  across 
northern  Arizona  to  the  Colorado  and  Mojave  deserts  in  California  as  far  west  as 
Tehachapi  Pass;  not  common.     Type  locahty,  California.     Collections:  Arizona,  1902, 

'  Throughout  the  paper  the  length  of  the  corolla  is  taken  to  include  the  lobea.  All  meaaurements  are  for  fresh  material 
or  for  flowers  restored  by  boiling. 


176  GENUS   CHRYSOTHAMNUS. 

Stephens;  California:  Chucka walla  Bench,  Colorado  Desert,  Schellenger  19  (UC); 
between  Cabezon  and  Whitewater,  Parish  651  (Gr,  UC,  US);  near  Bagdad,  southern 
Mojave  Desert,  May  20,  1902,  Brandegee  (UC);  eastern  slopes  of  Tehachapi  Pass,  Hall 
10961  (UC);  Resting  Springs  Valley,  Inyo  County,  Coville  and  Funston  280  (US). 

SYNONYMS. 

1.  BiGELOViA  PANICULATA  Gray,  Proc.  Am.  Acad.  8 :  644, 1873.  The  first  publication  with  a  description  of  C. 
paviculatus. 

2.  Ericameria  PANICULATA  Rydberg,  Fl.  Rocky  Mts.  853,  1917.     Based  upon  Bigelovia  paniculata. 

3.  LiNosrais  (Chrysothamnus)  viscidiflora  var.  paniculata  Gray,  Bot.  Mex.  Bound.  80,  1859.  This 
was  the  first  publication  of  the  name,  but  it  was  not  accompanied  by  a  description. 

RELATIONSHIPS. 

Because  of  its  similarity  to  species  of  Haplopappus  section  Ericameria,  especially  in 
the  resinous-punctate  herbage,  this  is  taken  as  one  of  the  most  primitive  of  the  Chryso- 
thamni,  and  hence  it  stands  first  in  the  taxonomic  sequence.  It  differs  from  all  species 
of  Haplopappus  in  the  vertical  arrangement  of  the  involucral  bracts  and  in  the  narrow 
heads,  while  from  the  species  which  are  most  like  it  in  other  respects  it  differs  also  in  the 
absence  of  ray-flowers.  Its  habitat  in  the  southwestern  deserts,  where  it  borders  upon 
the  areas  inhabited  by  species  of  Ericameria,  also  argues  for  its  former  connection  with 
that  group.  The  characters  of  C.  paniculatus  are  remarkably  constant,  at  least  as  far 
as  indicated  by  the  specimens  at  hand.  The  length  of  corolla  varies  by  only  0.2  mm., 
or  less  than  5  per  cent,  as  contrasted  with  variations  of  3  to  6  mm.,  or  about  100  per 
cent  in  some  of  the  more  plastic  species  (table  17).  In  relative  length  of  style-appendage 
and  stigmatic  portion,  however,  the  variation  is  nearly  as  great  as  in  the  most  variable 
species,  namely,  C.  nauseosus.  In  most  other  floral  characters  and  in  vegetative  features 
the  plants  show  but  little  fluctuation.  In  Brandegee's  specimens  from  Bagdad,  cited 
above,  the  inflorescence  is  very  narrow,  almost  racemose  in  fact,  but  aside  from  this 
collection  there  are  no  variations  of  consequence  and  there  have  been  no  attempts  to 
segregate  the  species  into  varieties  or  other  divisions.  This  remarkable  uniformity  is  no 
doubt  due  in  part  to  the  restricted  distribution  of  C.  paniculatus  and  suggests  that  this 
species  is  much  more  primitive  than  the  more  plastic,  variable  and  aggressive  ones  at 
the  opposite  end  of  the  genus. 

ECOLOGY  AND  USES. 

Chrysothamnus  paniculatus  is  a  rare  species  of  little  ecological  significance.  In  life- 
form  it  is  a  bush,  flowering  from  May  to  October.  It  is  subclimax  in  position,  occurring  in 
rocky  streamways  with  Lepidospartum  squamatum,  Hymenoclea  salsola,  and  Encelia 
frutescens,  or  with  one  or  more  of  them,  usually  in  the  Larrea-Yucca  ecotone. 

It  seems  unlikely  that  commercial  products  will  ever  be  obtained  from  this  plant. 
The  scarcity  of  the  supply  would  alone  prevent  the  utilization  of  the  wild  shrubs.  It  is 
possible,  however,  that  through  selection,  and  especially  through  cross-breeding  with 
C.  teretif  alius,  a  rubber  plant  might  be  discovered  with  sufficient  promise  to  warrant  cul- 
tivation on  a  commercial  scale.  The  rubber-content  of  wild  plants  has  been  found  to 
average  only  about  2.5  per  cent,  but  there  is  reason  to  believe  that  strains  or  at  least 
individuals  can  be  found  that  will  run  much  higher  than  this.  The  large  size  of  the 
shrubs,  their  resistance  to  low  temperatures,  and  their  ability  to  grow  in  the  poorest  of 
soil  where  the  water  content  is  exceedingly  low,  are  all  characteristics  highly  desirable 
in  rubber  plants.     The  nature  of  the  product  will  be  taken  up  under  the  next  species. 

2.    CHRYSOTHAMNUS  TERETIFOLIUS  (Durand  and  Hilgard)  Hall,  Univ.  Calif. 
Publ.  Bot.  3 :  57,  1907.     Plate  24. 

Shrub  3  to  9  dm.  or  rarely  even  20  dm.  high,  irregularly  much  branched  and  spreading 
to  form  a  flattish  or  rounded  bushy  plant;  bark  of  main  stems  dark  gray,  more  or  less 


C.    TERETIFOLIUS.  177 

grooved;  twigs  brittle,  erect,  very  leafy,  glabrous  but  resinous,  at  first  green  (or  with  a 
gray  bloom)  and  impressed-punctate,  later  turning  to  a  rich  reddish-brown  and  becoming 
striate;  leaves  terete,  obtuse,  not  mucronate,  1  to  2  cm.  long  (only  moderately  shorter  in 
the  inflorescence),  glabrous  but  resinous  and  marked  by  numerous  impressed  resin-dots, 
rarely  with  a  gray  waxy  bloom ;  heads  in  short  terminal  spikes,  these  apparently  cymose 
when  very  short,  or  thyrsoid  when  slightly  compound;  involucre  6  to  8  mm.  high;  bracts 
16  to  20,  in  5  sharply  defined  vertical  ranks,  oblong,  obtuse  or  the  inner  ones  shortly 
acute,  obscurely  carinate,  thinnish,  glabrous,  straw-colored,  with  a  conspicuous  green  or 
brownish  thickened  spot  near  apex,  often  terminated  by  a  thick  resin-gland;  flowers  5  or 
6;  corolla  tubular-funnelform,  the  tube  passing  gradually  to  the  moderately  dilated 
throat,  6  to  6.5  mm.  long,  glabrous;  lobes  lanceolate,  about  1  mm.  long,  erect  or  the  tips 
slightly  recurved,  glabrous;  anther-tips  linear,  acute,  0.6  mm.  long;  style-branches  long- 
exserted,  the  appendage  shorter  than  or  only  moderately  exceeding  the  stigmatic  portion; 
achenes  slender, slightly  tapering  from  summit  to  base,  5-angled, about  5  mm.long  when 
mature,densely  villous;  pappus  equaling  the  corolla  or  slightly  shorter,  white.  {Linosyris 
teretifolia  Durand  and  Hilgard,  Jour.  Acad.  Nat.  Sci.  Phila.  II,  3:41,  1855.) 

On  gravelly  or  stony  hillsides,  often  in  rocky  cafion  bottoms  from  central  Nevada  west 
and  south  to  the  easterly  basal  slopes  of  the  Sierra  Nevada  and  Tehachapi  Mountains, 
and  San  Gorgonio  Pass,  in  California;  perhaps  also  in  northern  Arizona;  most  abundant 
in  the  White  and  Inyo  Ranges  of  eastern  California.  Type  locality,  all  over  the  moun- 
tains around  Tejon  Valley,  California.  Collections:  Pancake  Range,  Nevada,  Purpus 
6S95  (UC,  US);  Lida,  western  Nevada,  Hall  10817  (SF,  UC);  Soda  Springs  Canon, 
western  Nevada,  Shockley  556  (Gr);  California:  easterly  slope  of  the  White  Mountains, 
Hall  10821  (UC);  Surprise  Canon,  Panamint  Mountains,  Coville  and  Funston  596  (US); 
Rosamond  Hills,  Antelope  Valley,  Hall  10572  (UC);  type  collection,  September,  1853, 
Heermann  (Gr);  San  Gorgonio  Pass,  Parish  655  (Gr). 

SYNONYMS. 

1.  BiGELOViA  TERETIFOLIA  Gray,  Proc.  Am.  Acad.  8:644,  1873. — C.  teretifolitis. 

2.  Linosyris  TERETIFOLIA  Durand  and  Hilgard,  Jour.  Acad.  Nat.  Sci.  Phila.  II,  3:41,  1855. — C.  teretifolius. 
This  was  the  first  publication  of  the  species.  It  was  soon  repeated  in  connection  with  an  excellent  plate  pub- 
lished by  the  same  authors  (Pacif .  R.  R.  Rep.  5' :  9,  pi.  7,  1856),  but  no  additional  information  was  there  given. 

RELATIONSHIPS. 

There  can  be  no  doubt  that  this  species  is  mostly  closely  related  to  C.  paniculatus, 
and  it  is  almost  equally  certain  that  it  represents  a  more  highly  developed  type  than  that. 
While  both  are  low  shrubs  of  the  desert  borders,  this  is  much  the  more  abundant  and 
widely  distributed,  and  is  thus  seen  to  be  a  more  successful  type.  The  inflorescence  is 
considered  as  a  reduction  from  the  more  branching  form  found  in  paniculatus,  the  heads 
are  narrower,  with  the  bracts  in  more  sharply  defined  vertical  ranks,  and  these  bracts 
show  further  specialization  in  the  strongly  marked  apical  or  subapical  green  spot  with  its 
resinous  exudate.  All  of  these  characters  are  taken  as  indicating  an  advance  over  the 
other  species.  As  in  that,  the  essential  features  are  remarkably  constant.  The  corollas 
are  only  slightly  more  variable  than  in  teretifolius  (table  17)  and  the  style-branches  much 
less  so.  The  plants  vary  much  in  size  and  habit,  but  this  is  correlated  with  environmental 
influences.  No  species  or  varieties  have  ever  been  proposed  as  segregates.  Such  con- 
siderations indicate  that  this  species  is  one  of  the  most  stable  of  the  genus  and  that  it  is 
not  producing  mutations  or  other  variations  that  might  serve  as  the  starting  point  of  new 
evolutionary  lines.  Its  position  among  the  more  primitive  species  is  attested  by  the 
absence  of  plasticity,  the  consequent  absence  of  variations,  and  the  restricted  distribu- 
tion, as  well  as  by  the  paucity  of  specialized  features. 


178  GENUS   CHRYSOTHAMNUS. 

ECOLOGY  AND  USES. 

Chrysothamnus  teretif alius  is  essentially  like  its  relative,  C.  paniculatus,  in  its  ecological 
behavior.  It  is  more  abundant  and  more  widely  distributed,  and  consequently  comes 
in  contact  with  the  sagebrush  association  as  well  as  with  the  Larrea  scrub.  It  is  likewise 
subclimax  in  nature,  but  is  found  more  frequently  on  gravelly  or  rocky  slopes  than  in 
streamways,  usually  with  Hymenodea  salsola. 

The  strongly  resinous  nature  of  its  herbage  precludes  the  use  of  this  species  as  a  browse 
shrub.  Its  only  other  possible  value  lies  in  the  fact  that  the  shrubs  contain  a  small 
amount  of  rubber.  While  this  averages  only  about  2.5  per  cent  in  wild  plants,  certain 
individuals  have  been  analyzed  that  ran  as  high  as  5  per  cent  (Hall  and  Goodspeed, 
Univ.  Calif.  Publ.  Bot.  7:267,  1919;  allowance  made  for  moisture  determination),  and 
there  is  no  reason  to  suppose  that  the  strains  richest  in  rubber  have  as  yet  been  located. 
The  total  yield  would  be  considerably  increased  by  any  method  of  mechanical  extraction, 
since  much  of  the  resin  would  come  out  with  the  rubber.  Such  a  product  would  be  of 
low  grade,  but  useful  as  a  rubber  substitute  if  it  could  be  placed  on  the  market  in  large 
quantities.  The  supply  of  native  shrub  is  not  sufficient  to  be  of  consequence  except  in  an 
emergency,  such  as  during  war-time,  when  importations  might  be  excluded,  but  the 
improvement  of  the  plants  through  selection,  breeding,  and  various  treatments  under  field 
conditions  might  result  in  a  product  and  yield  so  favorable  that  their  cultivation  as  a 
rubber  crop  could  be  successfully  undertaken  even  in  times  of  peace.  For  this  purpose, 
however,  some  of  the  forms  of  C.  nauseosus  are  more  promising. 

Section  II.    TYPICI. 
3.  CHRYSOTHAMNUS  GRAMINEUS  Hall,  Muhlenbergia,  2:342,  1916.    Plate  25. 

Plant  about  3  dm.  high,  woody  at  base  but  scarcely  shrubby;  twigs  probably  brittle, 
stiflBy  erect  or  ascending,  greenish-white,  striate;  leaves  lanceolate,  acuminate,  flat, 
4  to  6.5  cm.  long,  5  to  10  mm.  wide,  3-  to  5-nerved,  some  with  faint  anastomosing  veinlets, 
rigid,  the  margins  scabrous,  otherwise  glabrous  or  only  minutely  granular;  heads  soUtary, 
or  few  in  a  very  open  raceme;  involucre  about  11  mm.  high;  bracts  about  15,  the  vertical 
ranks  not  obvious,  oblong,  erose  at  the  obtuse  summit  except  the  outer  slenderly  mucro- 
nate  ones,  chartaceous  and  glabrous  except  the  outer  which  are  greenish  towards  the 
summit  and  ciliate;  flowers  4  to  5;  corolla  narrowly  funnelform,  12  mm.  long,  glabrous; 
lobes  1  to  1.7  mm.  long,  erect,  glabrous;  anther-tips  attenuate,  about  0.6  mm.  long; 
style-branches  long-exserted,  the  appendage  over  twice  as  long  as  the  stigmatic  portion; 
achenes  nearly  terete,  6  mm.  or  more  long,  10-striate,  glabrous;  pappus  nearly  equaling 
the  corolla,  brownish. 

Known  only  from  the  type.  Type  locality,  head  of  Lee  Canon,  Charleston  Mountains, 
Clark  County,  Nevada,  altitude  2,450  meters.  Collection,  tjrpe,  August  4,  1913,  A.  A. 
Heller  11076  (UC). 

RELATIONSHIPS. 

The  position  of  this  exceptionally  rare  species  in  the  phylogenetic  sequence  is  very 
uncertain.  Its  remarkably  striate  achenes  are  almost  exactly  like  those  of  C.  vaseyi, 
but  in  almost  every  other  detail  it  is  at  variance  with  that  species.  Except  for  the 
number  of  striae,  the  achenes  closely  resemble  those  of  the  otherwise  very  different 
C.  nauseosus  leiospermus.  The  long  stylar  appendages  and  the  subracemose  inflorescence 
suggest  an  alliance  with  C.  parryi,  but  the  habit,  the  glabrous  twigs,  and  especially  the 
glabrous  striate  achenes,  are  unlike  any  member  of  that  group.  If  it  were  not  for 
the  Pulchelli  and  C.  vaseyi,  which  seem  to  relate  it  to  Chrysothamnus  because  of  the  striate 
achenes  in  all,  it  might  almost  as  well  go  into  the  genus  Petradoria  (that  is,  Solidago 
pumila),  which  it  much  resembles  in  habit,  but  even  there  it  would  be  at  variance  with 


C.    GRAMINEUS — C.    VASEYI.  179 

the  single  known  species  of  the  genus,  which  has  flattish  5-nerved  achenes,  punctate 
leaves,  and  other  characters  not  found  in  gramineus.  The  latter  is  almost  exactly 
matched  in  foliage  characters  by  a  plant  collected  in  southern  Utah  by  Jones  and  named 
by  him  as  Bigelovia  menziesi  var.  scopulorum  (Proc.  Calif.  Acad.  II,  692,  1895).  While 
great  importance  can  not  be  attached  to  leaf  characters,  the  similarity  in  this  instance 
may  be  of  more  than  ordinary  significance,  for  the  type  of  leaf  is  entirely  different  from 
that  of  any  other  Chrysothmnnus,  or  indeed  from  that  of  any  member  of  any  closely 
related  genus.  Professor  Jones's  variety  was  later  taken  by  Greene  as  the  type  of  his 
new  genus  Hesperodoria  (Greene,  Leaflets  1:173,  1906).  Still  later  it  was  referred  to 
Isocoma  as  /.  scopulorum  (Rydberg,  Fl.  Rocky  Mts.  859,  1917).  Thus,  it  has  always 
been  considered  a  member  of  the  Haplopappus  group  of  genera  or  subgenera  rather  than 
of  Chrysothamnus.  The  present  emphasis  upon  the  similarity  between  its  foliage  and 
that  of  C.  gramineus  should  not  be  taken  as  more  than  suggestive,  unless  additional 
evidence  is  found  as  to  their  consanguinity.  The  heads  in  scopulorum  are  turbinate, 
rather  than  subcylindric,  as  in  gramineus,  the  flowers  are  nearly  twice  as  long  and  more 
than  twice  as  numerous,  and  the  achenes  are  4-  or  5-angled  and  densely  hispid,  as  con- 
trasted with  the  glabrous,  lO-striate  achenes  of  gramineus. 

The  conclusion,  therefore,  is  that,  although  C.  gramineus  is  anomalous  in  Chrysothamnus, 
chiefly  because  of  the  peculiar  foliage  and  the  lack  of  a  vertical  arrangement  of  its  bracts, 
it  would  be  still  more  aliomalous  in  any  other  genus,  and,  furthermore,  the  cylindric 
involucre  and  the  presence  of  similar  achenes  in  other  undoubted  members  of  the  genus 
leave  no  alternative  to  its  acceptance  as  a  member  of  Chrysothamnus. 

ECOLOGY  AND  USES. 

Chrysothamnus  gramineus  is  an  exceedingly  rare  undershrub,  flowering  from  August 
to  October.  It  grows  in  yellow-pine  savannah  as  a  secondary  species,  but  is  altogether 
too  sparse  to  be  of  importance  in  the  community.     It  has  no  known  uses. 

4.  CHRYSOTHAMNUS  VASEYI  (Gray)  Greene,  Erythea,  3:96,  1895.     Plate  25. 

Shrub  1  to  3  dm.  high,  single-stemmed  at  base,  but  soon  branching  to  form  a  low, 
rounded  bush;  bark  of  old  stems  brown,  fibrous;  twigs  brittle,  erect  or  ascending  with  a 
pale  green  or  whitish  glabrous  bark;  leaves  linear  or  very  narrowly  oblanceolate,  flat 
but  sometimes  twisted,  obtuse,  1  to  2.5  cm.  long,  1  to  2.5  mm.  wide,  l-nerved,  firm, 
glabrous  but  resinous-glandular;  heads  in  small,  compact  cymes;  involucre  5.5  to  7  mm. 
high;  bracts  about  15,  the  vertical  ranks  vaguely  defined,  oblong,  obtuse,  obscurely 
keeled,  glabrous  but  viscid-glandular  and  with  the  thin  white  margins  erose  or  ciliolate, 
the  outer  ones  with  a  thickened  greenish  spot  near  the  apex;  flowers  5  to  7;  corolla  tubular- 
funnelform,  passing  gradually  from  a  narrow  tube  to  a  much  wider  throat,  5.5  to  6.5  mm. 
long,  glabrous  or  only  minutely  granular;  lobes  linear-lanceolate,  1.5  to  2  mm.  long,  more 
or  less  spreading,  glabrous;  anther-tips  lanceolate,  acute,  0.5  to  0.8  mm.  long;  style- 
branches  slightly  exserted,  the  thick  appendage  usually  shorter  than  or  only  slightly 
exceeding  the  stigmatic  portion;  achenes  terete- turbinate,  about  5  mm.  long,  longitud- 
inally striate  with  about  10  nerves,  glabrous  or  rarely  with  a  very  sparse  pubescence  near 
summit,  smooth  and  shining  or  only  minutely  granular;  pappus  scant,  soft,  shorter  than 
the  mature  corolla,  dull  white.     (Bigelovia  vaseyi  Gray,  Proc.  Am.  Acad.  12:58,  1876.) 

In  mountain  valleys  and  on  hillsides  from  southern  Wyoming  and  New  Mexico 
to  Utah.  Type  locality,  Colorado,  in  Middle  Park.  Collections:  Laramie  Hills, 
Wyoming,  Nelson  6331  (Gr,  NY,  US);  type  collection,  1868,  Vasey  (Gr,  US); 
Ridgway,  Ouray  County,  Colorado,  Pay  son  2315  (SF);  Gunnison,  Colorado,  Baker  673 
(DS,  Gr,  NY,  UC,  US);  Montezuma  Canon,  southeastern  Utah,  Rydberg  and  Garrett 
9679  (NY,  UC,  US) ;  Panguitch  Lake,  Utah,  Jones  5998  (NY^  UC,  US);  slope  of  Aquarius 


180  GENUS   CHRYSOTHAMNUS. 

Plateau,  Utah,  Ward  630  (US);  Chama,  northern  New  Mexico,  September  5,  1899, 
Baker  652  (NY,  US,  type  collection  of  C.  bakeri  Greene,  minor  variation  2) ;  near  Dulce, 
Rio  Arriba  County,  New  Mexico,  Standley  81 84  (US). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  BiGEi.oviA  VASEYi  Gray,  Proc.  Am.  Acad.  12:58,  1876. — C.  vaseyi. 

2.  Chrysothamnus  bakeri  Greene,  Pittonia  4:152,  1900.— Described  from  plants  collected  by  Baker  near 
Chama,  New  Mexico,  and  compared  with  C.  greenei,  from  which,  however,  it  differs  in  the  obtuse  bracts,  gla- 
brous achenes,  and  other  characters.  On  the  other  hand,  specimens  of  the  type  collection  are  exactly  like  the 
usual  form  of  C.  vaseyi,  which  was  probably  overlooked  when  bakeri  was  diagnosed. 

RELATIONSHIPS. 

This  species  is  well  separated  phylogenetically  from  all  of  the  others,  as  is  especially 
indicated  by  the  character  of  its  achenes  and  of  its  style-branches.  Greene  has  already 
pointed  out  (Erythea  3:96,  1895)  that  the  former  are  longitudinally  10-striate.  They 
are  therefore  unlike  any  others  in  the  genus  except  in  the  Pulchelli  and  in  the  recently 
described  C.  gramineus.  The  style-branches  are  of  a  peculiar  shape.  Although  plainly 
flattened,  the  short,  thick,  somewhat  rounded  appendage  gives  them  the  appearance  of 
being  almost  club-shaped.  This  appendage  is  shorter  in  proportion  to  the  stigmatic 
part  than  in  any  other  Chrysothamnus,  except  in  occasional  specimens  of  C  greenei. 
It  is  to  this  species  that  vaseyi  is  probably  most  closely  related,  as  is  indicated  by  the 
appearance  and  by  the  general  assemblage  of  characters  as  well  as  by  the  style-branches. 
However,  even  this  alliance  can  not  be  very  close,  because  of  the  very  short,  angular 
achenes  and  abruptly  acute  bracts  of  greenei.  There  is  a  close  similarity  in  appearance 
between  this  species  and  certain  subspecies  of  C.  viscidiflorus,  such  as  pumilus,  but 
this  is  only  superficial,  as  is  indicated  by  the  important  differences  in  the  achenes  and 
style-branches  already  referred  to.  A  comparison  with  Petradoria  pumila  has  been  sug- 
gested, and  it  is  possible  that  there  is  some  connection  between  these  two  species  and 
also  between  them  and  the  true  Bigelovias,  that  is,  Chondrophora  of  some  botanists. 
Petradoria,  however,  is  an  herb  with  radiate  heads,  subulate  style-appendages,  and 
flattish  5-nerved  achenes,  while  the  true  Bigelovias,  also  herbs,  differ  from  C.  vaseyi 
in  a  number  of  characters,  as  pointed  out  in  the  introduction  (see  p.  157).  Chrysothamnus 
vaseyi  is  fairly  consistent  and  non-variable,  as  is  indicated  by  the  fact  that  no  segregate 
species  or  varieties  have  been  described,  with  the  single  exception  of  C.  bakeri  Greene, 
and  that  apparently  through  an  oversight,  as  already  mentioned. 
ECOLOGY  AND  USES. 

Chrysothamnus  vaseyi  occurs  in  grassy  mountain  parks  at  altitudes  of  6,000  to  8,500 
feet,  for  the  most  part  forming  societies  in  the  mixed  prairie.  In  southwestern  Colorado 
and  adjacent  Utah,  it  is  associated  with  the  sagebrush.  It  is  a  low  undershrub,  blooming 
during   August   and   September. 

It  is  unlikely  that  any  considerable  use  can  be  made  of  C.  vaseyi.  The  plants  are 
doubtless  browsed  by  sheep,  but  they  are  quite  small  and  apparently  nowhere  abundant. 

5.  CHRYSOTHAMNUS  VISCIDIFLORUS  (Hooker)  Nuttall,  Trans.  Am.  PhU.  Soc.  II. 
7 :  324,  1840.     Plates  26  and  27. 

Shrub  of  exceedingly  diverse  habit,  1  to  12  or  even  to  24  dm.  high,  commonly  much 
branched  from  the  simple  base  and  forming  a  round- topped  bushy  plant;  bark  of  the 
main  stems  brown,  fibrous;  twigs  brittle,  erect,  leafy,  glabrous  or  minutely  puberulent, 
with  a  pale  green  or  white  bark,  striate;  leaves  narrowly  linear  to  oblong  or  lanceolate, 
often  considerably  twisted,  acute  or  obtuse,  1  to  6  cm.  long,  1  to  10  mm.  wide,  1-  to 
5-nerved,  rather  rigid,  glabrous  or  puberulent,  viscidulous,  the  margins  commonly  sca- 
brous; heads  in  terminal  rounded  or  flat-topped  cymes;  involucre  5  to  8  mm.  high;  bracts 


C.    VISCIDIFLORUS.  181 

about  15,  in  poorly  defined  vertical  ranks,  broadly  to  linear  oblong  or  lanceolate,  acute 
or  obtuse,  firmly  chartaceous,  glabrous  or  minutely  pubenilent,  the  outer  ones  sometimes 
with  a  greenish  thickened  spot  near  the  apex ;  flowers  about  5 ;  corolla  tubular-funnelf orm, 
passing  gradually  from  tube  to  throat,  4.5  to  7  mm.  long,  glabrous  or  only  viscidulous; 
lobes  1  to  2  mm.  long,  erect  to  recurved-spreading,  glabrous ;  anther-tips  lanceolate,  acute, 
about  0.5  mm.  long;  style-branches  short-exserted,  the  lanceolate  acutish  appendage  one- 
half  to  three-fourths  as  long  as  the  stigmatic  portion;  achenes  narrowed  toward  the 
base,  5-angled,  3  to  4  mm.  long  at  maturity,  densely  to  sparsely  villous  or  silky;  pappus 
slightly  exceeding  the  corolla,  of  comparatively  rigid  sordid  bristles.  {Crinitaria  ins- 
cidiflora  Hooker,  Fl.  Bor.  Am.  2:24,  1834.) 

Plains  and  mountains  of  western  North  America,  on  poor  soil,  North  Dakota  to  New 
Mexico,  eastern  California,  British  Columbia,  and  Montana. 

SUBSPECIES. 
The  specific  limits  of  C.  viscidiflorus  as  here  adopted  are  the  same  as  those  set  by  Gray  in 
1873  (Proc.  Am.  Acad.  8:645,  as  Bigelovia  douglasi).  From  this  assemblage  of  forms 
there  have  been  published  from  time  to  time  a  total  of  20  segregates,  16  of  which  have 
been  accorded  specific  rank  by  those  who  use  a  narrow  species  concept.  Even  after  these 
17  proposals  have  been  reduced  to  10  subspecies,  it  is  found  that  they  pass  so  insensibly 
from  one  to  another  that  they  can  not  be  satisfactorily  defined.  It  is  believed,  however, 
that  the  following  artificial  key  and  the  descriptions  will  enable  one  to  place  a  majority 
of  the  specimens  as  they  come  to  hand. 

Key  to  Subspecies  of  Chrysoihamnus  viscidiflorus. 

Herbage  densely  puberulent,  especially  in  the  inflorescence,  and  the  leaves  2.5  to  6  mm. 

wide.     (Shrub  either  low  or  tall.) (a)  lanceolatus  (p.  181). 

Herbage  glabrous  or  if  pubescent  the  leaves  then  2  mm.  or  less  wide. 
Shrubs  low,  mostly  1  to  4  dm.  high;  leaves  only  1  to  2  mm.  wide. 
Bracts  without  distinctly  thickened  tips. 

Leaves  linear,  1  to  2  mm.  wide  and  the  herbage  glabrous (b)   pumilus  (p.  182). 

Leaves  linear-filiform  and  only  1  mm.  or  less  wide  or  if  wider  the  herbage  puberulent. 
Twigs  and  leaves  densely  puberulent. 

Leaves  linear-filiform,  1  mm.  wide (c)   puberulus  (p.  182). 

Leaves  linear  or  linear-oblanceolate,  1  to  2  mm.  wide (d)  humilis  (p.  182). 

Twigs  and  leaves  glabrous (e)   stenophyllus  (p.  183) 

Bracts  with  a  thickened  green  spot  at  tip if)   elegans  (p.  183). 

Shrubs  taller,  mostly  4  to  24  dm.  high;  leaves  2  to  10  mm.  wide  (rarely  narrower  in 
typicus).     Herbage  glabrous. 
Bracts  thin,  without  a  distinct  greenish  subapical  spot;  plants  of  non-alkaline  soils. 

Leaves  1  to  4  mm.  wide,  1-  to  3-nerved (g)  typicus  (p.  183). 

Leaves  4  to  10  mm.  wide,  3-  or  5-nerved (h)  latifolius  (p.  184). 

Bracts  thicker  (at  least  the  outer  ones)  with  a  conspicuous  greenish  or  brownish  spot 

near  the  obtuse  summit;  plants  of  alkaUne  soils (i)   linijolius  (p.  184). 

5a.  Chrysothamnus  viscidtflorus  lanceolatus  (Nuttall).  Low  or  medium-sized 
shrub,  2  to  5  dm.  high  or  rarely  more;  leaves  broadly  linear  or  linear-lanceolate,  abruptly 
acute,  1.5  to  4  cm.  long,  2.5  to  6  mm.  wide,  3-nerved  or  5-nerved,  usually  not  twisted, 
bright  green,  at  least  the  upper  ones  densely  rough-puberulent;  cyme  small,  compact,  its 
branches  densely  puberulent;  involucre  5  to  6.5  mm.  high;  bracts  oblong,  scarcely  keeled, 
rather  obtuse,  without  subapical  spot;  achenes  densely  strigose.  (C.  lanceolatus  Nuttall, 
Trans.  Am.  Phil.  Soc.  II,  7:324,  1840.)  Montana  to  Colorado,  Nevada,  Washington, 
and  Idaho.  Type  locality,  in  the  Rocky  Mountains,  toward  the  sources  of  the  Platte. 
Collections:  Helena,  Montana,  September  16,  1891,  Kelsey  (UC);  Nowood  Creek,  Big 
Horn  County,  Wyoming,  Goodding  509  (Or,  NY,  UC,  US) ;  Hayden,  Routt  County,  Colo- 
rado, Goodding  1791  (DS,  Gr,  NY,  UC,  US);  Mackay,  Custer  County,  Idaho,  Nelson  and 
Machride  1525  (Gr,  NY,  UC) ;  Castle  Gate,  Utah,  Jones  5486i  (US) ;  banks  of  the  Colum- 
bia River  at  Grants,  Oregon,  September  15,  1887,  Howell  (UC,  tall  form);  Coulee  City, 
Washington,  Lake  and  Hull  732  (Gr,  tall  form). 


182  GENUS   CHRYSOTHAMNUS. 

56.  Chrtsothamnus  viscidiflorus  pumilus  (Nuttall). — Shrub  1  to  5  dm.  high; 
leaves  linear,  pungently  acute,  2  to  4  cm.  long,  1  to  2  mm.  wide,  1-nerved  or  often 
3-nerved,  plane  or  tortuous,  bright  green,  viscidulous  or  slightly  glandular  and  the 
margins  sometimes  scabrid,  otherwise  glabrous;  cyme  small  but  sometimes  lax,  its 
branches  glabrous;  involucre  5  to  6  mm.  high;  bracts  oblong,  not  keeled,  the  outer  ones 
acute,  the  inner  obtuse  or  submucronate,  all  devoid  of  subapical  spot;  achenes  moderately 
or  densely  strigose.  (C.  pumilus  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:323,  1840,  in  part, 
namely,  as  to  the  smooth  plants.)  Plains  and  foothills,  Montana  to  Colorado,  Utah, 
eastern  California,  and  Washington.  Type  locality,  on  the  borders  of  Lewis  River 
and  the  Rocky  Mountain  Plains.  Collections:  Type  collection.  Rocky  Mountains, 
Nuttall  (Phila.);  Sedan,  Gallatin  County,  Montana,  August  10,  1902,  W.  W.  Jones 
(Gr);  Wamsutter,  southwestern  Wyoming,  August  IS,  1894,  Wooton  (US);  Laramie, 
southeastern  Wyoming,  Nelson  6861  (NY);  head  of  Poison  Creek,  Utah,  Rydberg  and 
Carlton  7435  (NY);  Bear  Valley,  San  Bernardino  Mountains,  California,  Abrams  2889 
(UC);  Sonora  Trail,  easterly  slope  of  the  Sierra  Nevada,  California,  State  Survey  1859 
(UC,  an  unusual  variation  with  broad  involucres  only  4.5  mm.  high,  the  bracts  very 
obtuse);  near  Hay  Fork  Post  Office,  Crook  County,  Oregon,  Leiberg  862  (US,  inter- 
mediate to  stenophyllus;  leaves  1  to  1.5  mm.  wide);  Spokane,  Washington,  Kreager 
613  (NY);  Pocatello,  Idaho,  July  30,  1889,  Greene  (UC). 

5c.  Chrysothamnus  viscidiflorus  puberulus  (D.  C.  Eaton). — Low  shrub,  2  to  5 
dm.  high;  leaves  narrowly  linear,  acute,  1.5  to  4  cm.  long,  rarely  over  1  mm.  wide, 
1-nerved,  often  twisted  or  revolute,  pale  grayish-green,  densely  puberulent;  cyme  small, 
compact  (occasionally  looser  and  up  to  7  cm.  broad),  its  branches  densely  puberulent; 
involucre  about  6  mm.  high;  bracts  oblong,  not  keeled,  obtuse  or  the  outer  barely 
acute,  devoid  of  subapical  spot;  achenes  densely  strigose  or  silky.  (Linosyris  viscidi- 
flora  var.  puberula  Eaton,  Bot.  King's  Expl.  158,  1871.)  Montana  to  Colorado,  eastern 
California,  and  British  Columbia;  abundant  on  dry  hills  and  in  dry  streamways  of 
Nevada.  Type  locality,  near  the  Truckee  and  on  the  Hot  Springs  Mountains  in 
western  Nevada.  Collections :  Type  collections,  Truckee  Valley,  northwestern  Nevada, 
July,  1867,  W.  W.  Bailey  569  (Gr,  US),  and  West  Humboldt  Mountains,  northwestern 
Nevada,  1,900  m.  altitude,  September,  1867,  Watson  569  (Gr);  Crook  Creek,  Fremont 
County,  Wyoming,  Goodding  524  (UC,  nearly  glabrous,  distributed  as  C.  pumilus); 
Sevier  River,  below  Marysvale,  Utah,  Rydberg  and  Carlton  6993  (NY,  type  of  C.  maria- 
nus  Rydberg,  minor  variation  22);  Caliente,  Nevada,  August  27,  1912,  Jones  (DS,  UC); 
Lander  County,  Nevada,  Kennedy  4533  (DS,  UC);  Mesa  west  of  Goldfield,  Nevada, 
Heller  10973  (DS,  Gr,  NY,  UC,  US) ;  Reno,  on  dry  banks  near  Truckee  River,  Nevada, 
Hall  10547  (UC);  Benton,Mono  County,  California,  Hall  10677  (UC);  near  Redmond, 
Oregon,  September  29,  1918,  Whited  (UC);  Crook  County,  Oregon,  Coville  and  Leiberg 
664,  732,  and  773  (US);  Shoshone,  Idaho,  Palmer  511  (NY). 

bd.  Chrysothamnus  viscidiflorus  humilis  (Greene). — Low  shrub,  commonly  only  1 
to  2  but  sometimes  3  dm.  high;  leaves  linear  or  slightly  oblanceolate,  1  to  2  cm.  long, 
1  to  2  mm.  wide,  1-nerved  or  an  occasional  leaf  with  3  nerves,  usually  plane,  very  pale 
or  grayish-green,  densely  puberulent;  cyme  usually  small  and  compact,  sometimes 
rather  loose  and  spreading,  its  branches  densely  puberulent;  involucre  6  to  7  mm.  high; 
bracts  oblong,  not  keeled,  obtuse,  devoid  of  subapical  spot;  achenes  densely  strigose. 
(C.  humilis  Greene,  Pittonia  3:24,  1896.)  Arid  plains  of  northeastern  California  and 
eastern  Oregon,  extending  into  western  Nevada.  Type  locality,  plains  of  the  Truckee 
River,  Nevada  County,  California.  Collections:  Type  collection,  sagebrush  plains  in 
Martis  Valley,  near  Truckee,  August,  1895,  Sonne  (Herb.  Greene,  NY,  UC);  Christmas 
Lake,  Lake  County,  Oregon,  Leiberg  772  (DS,  Gr,  UC,  US,  leaves  up  to  3  cm.  long); 


C.   \aSCIDIFLORUS.  183 

Silvies  Valley,  eastern  Oregon,  Cusick  2052  (UC,  distributed  as  Bigelovia  douglasi  var. 
pumila);  Carters,  western  middle  Nevada,  August  17,  1906,  Eastwood  (SF). 

5e.  Chrtsothamnus  viscidiflorus  stenophyllus  (Gray). — Shrub  1  to  3  dm.  high; 
leaves  very  narrowly  linear  or  linear-filiform,  rigidly  acute,  1  to  3  cm.  long,  1  mm.  or 
less  wide,  1-nerved,  often  tortuous,  pale  green,  viscidulous  or  glandular,  the  margins 
usually  scabrid  and  revolute,  the  faces  glabrous;  cyme  small,  compact,  its  branches 
glabrous;  involucre  4  to  6  mm.  high;  bracts  lance-oblong,  strongly  1-nerved,  not  keeled, 
abruptly  acute  or  mucronate,  devoid  of  subapical  spot;  achenes  densely  strigose. 
{Bigelovia  douglasi  var.  stenophylla  Gray,  Proc.  Am.  Acad.  8:646,  1873.)  Dry  ridges 
and  stony  slopes:  Montana  and  Wyoming  to  New  Mexico,  southern  California,  eastern 
Oregon,  and  Idaho.  Type  locality,  northwestern  Nevada.  Collections:  Livingston, 
Montana,  September,  1901,  Scheuber  (US);  Centennial  Valley,  Wyoming,  Nelson  1847 
(R,  type  of  C.  pumilus  varus  Nelson,  minor  variation  27);  Point  of  Rocks,  Wyoming, 
Nelson  8142  (Gr,  NY,  US);  type  collection,  Huntington  Valley,  at  1,830  m.  altitude, 
northwestern  Nevada,  August,  1868,  Watson  566  (Gr,  NY,  US);  San  Antonio  Desert, 
Nevada,  Purpus  6415,  in  part  (UC);  Candelaria,  western  Nevada,  Shockley  310  (UC, 
US) ;  vicinity  of  Cedar  Hill,  San  Juan  County,  New  Mexico,  Standley  7977  (US) ;  Bill- 
ings, Montana,  Jones  4512  (NY,  US);  Bear  Valley,  San  Bernardino  Mountains,  Cali- 
fornia, Grinnell  73  (UC,  leaves  3-nerved  and  plants  otherwise  approaching  subspecies 
pumilus) ;  near  Christmas  Lake,  southeastern  Oregon,  Leiberg  779  (Gr,  US) ;  Big  Butte 
Station,  Idaho,  Palmer  488  (NY,  US). 

5/.  Chrtsothamnus  viscidiflorus  elegans  (Greene). — Low  shrub,  1  to  4  dm. 
high;  leaves  linear,  pungently  acute,  1.5  to  3  cm.  long,  1  to  2  mm.  wide,  mostly  3-nerved, 
usually  much  twisted,  green,  scabrid-ciliolate,  the  upper  also  puberulent  on  the  faces; 
cyme  small,  compact,  its  branches  densely  puberulent ;  involucre  about  5  mm.  high ; 
bracts  lanceolate,  keeled,  acute  or  the  inner  ones  obtuse,  with  an  obscurely  thickened 
greenish  or  brownish  subapical  spot;  achenes  strigose.  (C.  elegans  Greene,  Erythea 
3:94,  1895.)  Plains  and  dry  valleys,  western  Wyoming  to  Colorado,  Arizona  and  Nevada; 
probably  also  in  New  Mexico,  but  aU  specimens  seen  from  there  and  labeled  elegans  are 
glabrous  and  belong  to  subspecies  typicus.  Type  locality,  Gunnison  Valley,  Colorado. 
Collections:  West  of  Evanston,  Wyoming,  September  13,  1919,  Hall  (CI);  near  Flo- 
rissant, Colorado,  September  2,  1919,  Clements  (CI);  type  collection,  1890,  Greene 
(Herb.  Greene,  UC) ;  Doyles,  west  central  Colorado,  Baker  643  (DS,  Gr,  NY,  UC,  US, 
some  leaves  glabrous);  between  Gunnison  and  Parlin,  Colorado,  September  1,  1918, 
Hall  (UC);  Grand  Canon  of  the  Colorado,  Arizona,  August,  1887,  Allen  (NY);  Ely, 
Nevada,  A.  E.  Hitchcock  1219,  in  part  (US). 

5^.  Chrsysothamnus  viscidiflorus  typicus. — Shrub  usually  5  to  12  dm.  high; 
leaves  narrowly  lanceolate  or  broadly  linear,  acute,  2  to  5  cm.  long,  2  to  5  mm.  wide 
(rarely  only  1  mm.),  1-nerved  in  the  original  form,  but  often  3-nerved,  either  plane  or 
twisted,  bright  green  or  bluish-green,  the  margins  entire  or  scabrous-ciliolate,  glabrous, 
viscid;  cyme  broad,  open,  its  branches  glabrous  but  glutinous;  involucre  5  to  7  mm. 
high;  bracts  boat-shaped,  not  keeled,  obtuse  but  commonly  mucronate  (acute  in  minor 
variation  29,  C.  stenolepis  Rydberg),  without  subapical  spot;  achenes  densely  villous. 
(Crinitaria  viscidiflora  Hooker,  Fl.  Bor.  Am.  2:24,  1834.)  Dry  plains  and  hillsides, 
often  among  rocks,  from  Montana  to  Wyoming,  Colorado,  Arizona,  eastern  California, 
and  Washington.  Type  locality,  on  the  barren  plains  of  the  Columbia,  from  the  Great 
Falls  to  the  mountains,  and  along  the  Salmon  River,  Northwest  America.  Collections 
(with  leaves  mostly  3-nerved):  Fridley,  Montana,  Rydberg  and  Bessey  5044a  (Gr); 
Chimney  Rock,  Medicine  Bow  Mountains,  Wyoming,  Nelson  2054  (R.  type  of  C. 
glaucus  Nelson,  minor  variation  16);  Laramie  Hills,  Wyoming,  Nelson  6308  (Gr,  NY, 


184  GENUS   CHRYSOTHAMNUS. 

UC,  US,  similar  variation  but  with  bracts  of  minor  variation  29);  Georgetown,  south- 
western Colorado,  Jones  744  (NY,  US,  same  variation) ;  near  Grand  Junction,  Colorado, 
August  27,  1896,  Greene  (Herb.  Greene,  type  of  C.  leucocladus  Greene,  minor  variation 
20);  Salt  Lake  Valley,  Utah,  (NY,  type  collection  of  Linosyris  serrulata  Torrey,  minor 
variation  42) ;  Oquirrh  Mountains,  Tooele  County,  Utah,  W.  W.  Jones  479  (Gr) ;  west 
of  Buckskin  Mountains,  Arizona,  Jones  6063g  (US) ;  Lee  Canon,  Charleston  Mountains, 
southwestern  Nevada,  Heller  11087  (Gr,  NY,  US);  San  Jacinto  Mountain,  southern 
California,  Nemn  (DS);  Truckee,  California,  Heller  7189  (DS,  NY,  US);  Bear  Buttes 
Pass,  Oregon,  Leiberg,  795  (Gr,  UC);  Fish  Hook  Ferry,  Oregon,  Leiberg  926  (UC); 
Redmond,  Oregon,  September  29,  1918,  Whited  (UC,  minor  variation  38);  Spokane 
County,  Washington,  Suksdorf  925  (Gr) ;  Mackay,  Custer  County,  Idaho,  Nelson  and 
Macbride  1559  (DS,  Gr,  UC);  Flint  Creek,  Owyhee  County,  Idaho,  Macbride  490 
(DS,  R). 

5/t.  Chrysothamnus  viscidiflorus  latifolius  (Eaton). — Shrub  3  to  10  dm.  high; 
leaves  broadly  elliptic  or  broadly  lanceolate,  obtuse  but  mucronate,  2  to  4  cm.  long, 
6  to  12  mm.  wide,  3-  or  5-nerved,  plane,  bright  green,  entire,  glabrous  or  the  margins 
merely  scabrous;  cyme  either  broad  and  lax  or  small  and  dense,  its  branches  glabrous; 
involucre  6  to  7  mm.  high;  bracts  not  keeled,  obtuse  or  acute,  without  subapical  spot; 
achenes  densely  villous.  {Linosyris  viscidiflora  var.  latifolia,  Eaton,  Bot.  King's  Expl. 
157,  1871.)  Southern  Idaho  and  western  Utah  across  Nevada  to  eastern  California 
and  Oregon.  Type  locality,  mountains  at  the  head  of  Humboldt  River,  Nevada,  at  an 
altitude  of  2,000  to  2,200  meters.  Collections:  Type  collection,  September,  1868, 
Watson  568  (Gr,  NY,  US);  West  Humboldt  Mountains,  Nevada,  Heller  10626  (DS,  Gr, 
UC,  US);  Gold  Creek,  Elko  County,  Nevada,  Kennedy  4398  (UC);  Modoc  County, 
California,  Gilman  520  (UC). 

bi.  Chrysothamnus  viscidiflorus  linifolius  (Greene). —  Shrub  8  to  24  dm.  high; 
leaves  lanceolate  to  oblong-lanceolate,  gradually  acute,  2  to  5  cm.  long,  4  to  8  mm.  wide, 
mostly  3-nerved,  plane,  bright  green,  glabrous,  entire  or  only  obscurely  scabrous  on  the 
margins;  cyme  broad,  lax,  its  branches  glabrous;  involucre  5  to  6  mm.  high;  bracts 
oblong,  not  keeled,  obtuse,  at  least  the  outer  with  a  thickened  subapical  spot,  this  green 
but  drying  to  brown;  achenes  densely  villous.  (C.  linifolius  Greene,  Pittonia  3:24, 
1896.)  On  low,  alkaline  lands,  Wyoming,  western  Colorado,  Utah,  and  New  Mexico. 
Type  locality,  in  moist,  alkaline  soil,  plentiful  along  a  streamlet  near  Rock  Springs, 
Wyoming.  Collections:  Type  collection,  August  9,  1895,  Greene  (Herb.  Greene);  Bitter 
Creek,  Wyoming,  Nelson  41 43  (UC);  Grand  Junction,  Colorado,  Baker  924  (Gr,  NY, 
UC,  US);  southeastern  Utah,  Rydberg  and  Garrett  9437  (UC);  Rabbit  Valley,  Utah, 
Ward  573  (Gr) ;  Cainville,  Utah,  Jones  5698  (NY) ;  near  Farmington,  San  Juan  County, 
New  Mexico,  Standley  6903  (US). 

MINOR  variations  AND  SYNONYMS. 

1.  BiGELOviA  DOUGLASI  Gray,  Proc.  Am.  Acad.  8:645,  1873. — C.  viscidiflorus  typicus. 

2.  B.  DOUGLASI  var.  lanceolata  Gray,  Syn.  Fl.  1=:140,  1884. — C.  viscidiflorus  lanceolatus. 

3.  B.  DOUGLASI  var.  latifolia  Gray,  Proc.  .\m.  Acad.  8:646,  1873. — C.  viscidiflorus  lalifolius. 

4.  B.  DOUGLAS!  var.  puberula  Gray,  1.  c. — C.  viscidiflorus  puberulus. 

5.  B.  DOUGLASI  var.  pumila  Gray,  Syn.  Fl.  P:140,  1884. — C.  viscidiflorus  pumilus. 

6.  B.  DOUGLASI  var.  serrulata  Gray,  Proc.  Am.  Acad.  8 :  646,  1873.^-Same  as  Linosyris  viscidiflora 
serrulata,  q. v. 

7.  B.  DOUGLASI  var.  spathulata  Jones,  Proc.  Calif.  Acad.  II,  5:690,  1895. — Authentic  material  not  seen,  but 
apparently  a  form  of  C.  viscidiflorus  lanceolatus  with  short  lower  leaves. 

8.  B.  DOUGiAsi  var.  stenophylla  Gray,  1.  c. — C.  viscidiflorus  stenophyllus. 

9.  B.  DOUGLASI  var.  tortifolia  Gray,  1.  c. — C.  viscidiflorus  and  its  subspecies.  First  applied  to  plants 
similar  to  subspecies  typicus,  but  with  the  leaves  twisted  upon  themselves,  later  extended  by  various  writers 
to  other  subspecies  in  which  this  trait  was  noticed  and  even  used  by  some  as  of  specific  value.  The  tendency 
toward  torsion  is  sometimes  indicated  only  by  an  undulation  of  the  margins  and  all  degrees  are  encountered  from 


C.    VISCIDIFLORUS.  185 

this  to  extreme  cases  in  which  a  blade  will  make  two  complete  revolutions  on  its  axis.  Since  this  character  is 
thus  variously  developed  and  fails  to  run  parallel  with  any  other  tendency,  and  since  it  is  encountered  in  all  of 
the  subspecies  (with  the  possible  exception  of  the  firm-leaved  linif alius),  it  is  not  here  considered  as  of  diagnostic 
value.  Especially  misleading  is  the  common  custom  of  identifying  any  specimen  with  tortuous  leaves  as  "tor- 
tifolius,"  quite  regardless  of  its  other  features. 

10.  B.  GLAUCA  Schumann,  Just's  Bot.  Jahresb.  26':  375,  1900. — Based  upon  C.  glaucm,  and  therefore  a  form 
of  C.  viscidifloriis  iypicus.     (See  No.  16  of  this  list.) 

ll._  B.  LANCEOLATA  Gray,  1.  c,  639,  1873. — C.  viscidiflorus  lanceolatus. 

12.'  B.  LiNiFOLiA  Nelson,  First  Rept.  Fl.  Wyo.  123,  1896.— C.  viscidiflorus  linifolim. 

13.  B.  visciDiFLORA  De  Candolle,  Prodr.  7:279,  1838. — Based  upon  Crinitaria  visddiflora  Hooker,  No.  39 
of  this  list. 

14.  Chrysothamnus  douglasi  Clements  and  Clements,  Rocky  Mt.  Fls.  266,  1914. — C.  viscidiflorus,  includ- 
ing several  of  the  subspecies. 

15.  C.  ELEGANS  Greene,  Erythea  3:94,  1895.— C.  viscidiflorus  elegans. 

16.  C.  GLAUCUS  Nelson,  Bull.  Torr.  Club  25:377,  1898. — A  glaucous-leaved  form  or  state  of  Linosyris 
visddiflora  serrulata  Torrey,  which  in  turn  is  here  considered  as  not  separable  from  C.  viscidiflorus  Iypicus  (see 
No.  42  of  this  list).  The  peduncles  are  sometimes  obscurely  puberulent.  Old  specimens  are  less  glaucous, 
according  to  Nelson  (Bot.  Gaz.  28:376,  1899).  The  heads  in  the  type  material  are  4-flowered,  as  originally 
described,  but  they  are  often  5-flowered,  as  in  Nelson's  5308  from  Laramie,  Wyoming,  and  in  Palmer's  257  from 
Wadsworth,  Nevada,  both  of  which  are  referable  here.  The  type  is  Nelson  2054  from  Chimney  Rock,  Medicine 
Bow  Mountains,  Wyoming. 

17.  C.  HUMiLis  Greene,  Pittonia  3:24,  1896. — C.  viscidiflorus  humilis. 

18.  C.  LANCEOLATUS  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:324,  1840.— C.  viscidiflorus  lanceolatus. 

19.  C.  LATiFOLius  Rydberg,  Bull.  Torr.  Club  33:152,  1906.— C.  viscidiflorus  Mifolius. 

20.  C.  LEUCOCLADUs  Greene,  Pittonia  5 :  59,  1902.— A  form  of  C.  viscidiflorus  iypicus  with  exceptionally  large 
heads  and  rather  narrow  leaves.  Said  by  Greene  to  be  near  elegans,  but  the  type  in  his  herbarium  does  not  have 
the  green  thickenings  on  the  bracts  characteristic  of  that  subspecies.  The  involucres  in  the  type  specimen  are 
7  to  8  mm.  long,  which  is  exceptionally  large,  even  for  Iypicus;  leaves  2  mm.  wide;  stems  of  unknown  height, 
the  portion  preserved  being  3  dm.  long,  but  consisting  only  of  leafy  flowering  branches.  Type  locality,  near 
Grand  Junction,  Colorado. 

21.  C.  LiNiFOLius  Greene,  Pittonia  3:24,  1896.— C.  viscidiflorus  linifolius. 

22.  C.  MARIANUS  Rydberg,  Bull.  Torr.  Club  37: 131,  1910.— The  type  specimens  at  the  herbarium  of  the  New 
York  Botanical  Garden  appear  to  be  identical  with  C.  visddiflorus  puherulus,  except  that  the  achenes  are  only 
sparsely  pubescent  or  nearly  glabrous.  The  original  description  of  the  leaves  and  bracts  applies  exactly  to  the 
common  form  of  puberulus.  The  type  locality  is  along  the  Sevier  River,  below  Marysvale,  Utah.  Most  of  the 
material  under  this  name  at  the  United  States  National  Herbarium  has  strongly  pubescent  achenes  and  belongs 
in  part  to  C.  visddiflorus  stenophyllus,  the  remainder  being  chiefly  C.  v.  elegans. 

23.  C.  PUBERULUS  Greene,  Erythea  3:93,  1895. — C.  visddiflorus  puberulus. 

24.  C.  PUMILUS  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:323,  1840.— C.  visddiflorus  pumilus. 

25.  C.  PUMILUS  /3  EUTHAMOiDEs  Nuttall,  1.  c.— A  form  of  C.  visddiflorus  pumilus  described  as  with  "involu- 
crum  ovate,  the  scales  ovate  and  short."  The  type  locality  was  not  indicated  as  different  from  that  of  pumilus 
and  the  type  specimens  have  not  been  found.  Perhaps  similar  to  this,  if  not  identical,  is  a  plant  from  the  Sonora 
Trail,  east  side  of  the  Sierra  Nevada,  California  (State  Survey  1859,  UC),  in  which  the  thick  involucre  is  scarcely 
5  mm.  high  and  the  scales  very  wide,  the  inner  ones  exceptionally  obtuse.  This  may  represent  a  subspecies 
distinct  from  pumilus. 

26.  C.  PUMILUS  var.  latus  Nelson,  Bot.  Gaz.  54:413,  1912.— An  exceptionally  broad  leaved  form  of  C.  vis- 
ddiflorus lanceolatus,  the  leaves  4  to  8  mm.  wide  in  the  types.  Very  distinct  from  pumilus,  not  only  in  the 
much  wider  leaves,  but  also  in  the  fine  but  dense  pubescence  of  the  twigs,  peduncles,  and  foliage.  The  type  is 
from  Ketchum,  Blaine  County,  Idaho,  Nekon  and  Macbride  1236  (R). 

27.  C.  PUMILUS  var.  varus  Nelson,  Bot.  Gaz.  28:375,  1899.— C.  visddiflorus  stenophyllus.  The  types  of 
these  have  been  closely  compared  and  no  difference  found  except  that  the  type  of  varus  is  a  fresher  and  greener 
specimen.  In  the  New  Rocky  Mountain  Manual,  by  Coulter  and  Nelson,  the  description  of  varus  is  extended 
to  include  C.  elegans  Greene,  but  this  subspecies  differs  markedly  in  its  densely  puberulent  inflorescence,  green- 
tipped  bracts,  and  wider  leaves.     The  type  of  varus  is  Nelson  1847  (R)  from  Centennial  Valley,  Wyoming. , 

28.  C.  SERRULATUs  Rydberg,  Bull.  Torr.  Club  33 :  152,  1906.— The  same  as  No.  42  of  this  list. 

29.  C.  sTENOLEPis  Rydberg,  1.  c,  37: 131,  1910.— A  perplexing  variation  apparently  referable  to  C.  visddi- 
florus Iypicus,  but  differing  in  the  narrower  and  very  acute  involucral  bracts.  The  type  specimen  (Pass  Creek, 
Bridger  Mountain,  Montana,  Engebnann,  NY)  has  "leaves  only  2  to  4  mm.  wide  and  is  described  as  a  low  shrub, 
2  to  3  dm.  high.  The  whole  aspect  of  the  plant,  with  its  narrow,  tmsted,  incurved  leaves  suggests  that  it  may 
be  the  response  to  a  cold,  dry  environment.  There  should  be  considered  in  this  connection  also  Nelson  6S08  (as 
to  the  glabrous  plants,  the  pubescent  ones  being  subspecies  lanceolatus)  from  the  Laramie  Hills,  Wyoming,  and 


186  GENUS   CHRYSOTHAMNUS. 

distributed  as  C.  glaucus  Nebon.    These  specimens  have  the  very  acute  bracts  of  stenolepis,  but  the  leaves  are 

mostly  flat,  3  mm.  wide,  and  the  shrubs  were  not  reduced  in  size.  Their  combination  of  characters  indicates  an 
intermediate  stage.  C.  stenolepis  is  worthy  of  detailed  studies  in  the  field,  where  it  may  be  found  that,  at  least 
as  far  as  the  type  form  is  concerned,  it  is  a  wide-leaved  and  narrow-bracted  variation  from  subspecies  pumilits. 

30.  C.  STENOPHYLLUs  Greene,  Erythea  3:94,  1895. — C.  viscidiflorus  stenophyllus. 

31.  C.  TORTiFOLius  Greene,  Fl.  Fran.  368,  1897. — C.  viscidiflorus  and  its  subspecies,  as  noted  under  No.  9. 

32.  C.  VISCIDIFLORUS  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:324,  1840.— C.  viscidiflorus  typicus. 

33.  C.  ^^scIDIFL0Rus  var.  lanceolatus  Greene,  Erythea  3 :  95,  1895. — C.  viscidiflorus  subspecies  lanceolatus. 

34.  C.  VISCIDIFLORUS  var.  latifolius  Greene,  1.  c.  96. — C.  viscidiflorus  subspecies  latifolius. 

35.  C.  VISCIDIFLORUS  var.  serrulatus  Greene,  1.  c. — The  same  as  No.  42  of  this  list. 

36.  C.  VISCIDIFLORUS  Var.  tortifouus  Greene,  1.  c. — Various  subspecies  of  C.  viscidiflorus  are  included  under 
this  name.     (See  No.  9.) 

37.  C.  VISCIDIFLORUS  TYPICUS,  but  with  comparatively  short  and  very  green  leaves.  This  form  grows  on 
sandy  flats  near  Chambers  Station,  northeastern  Arizona  {Hall  11151,  11152,  UC).  The  plants  are  4  to  7  dm. 
high,  woody  to  the  top,  the  twigs  erect  and  fastigiately  crowded;  leaves  1  to  2  mm.  wide,  1  to  2  cm.  long,  gla- 
brous and  green;  involucre  6  mm.  high;  bracts  in  distinct  vertical  rows,  acute,  greenish  but  without  definite  spot. 
Apparently  distinct  from  typical  viscidiflorus,  but  the  differences  are  superficial.  The  plants  show  evidence  of 
top-browsing,  which  may  account  for  their  fastigiate  habit,  and  the  reduction  in  leaf  may  be  the  result  of  unfa- 
vorable soil  conditions. 

38.  C.  VISCIDIFLORUS  TYPICUS,  but  with  leaves  only  0.5  to  1  mm.  wide.  This  variation  is  of  rare  occurrence 
and  may  be  more  than  a  response  to  ecologic  conditions.  The  extreme  form  is  represented  by  a  collection  from 
the  Snake  River  sands  north  of  Hagerman,  Idaho,  September  18,  1919,  Hall  (UC).  A  complete  series  of  inter- 
grading  forms  is  not  at  hand  but  as  intermediates  may  be  cited :  8  km.  southwest  of  Redmond,  Oregon,  Septem- 
ber 29,  1918,  Whited  (UC),  and  Grizzly  Butte  Spur,  eastern  Oregon,  Leiberg  855  (UC). 

39.  Crinitaria  viscidiflora  Hooker,  Fl.  Bor.  Am.  2:24,  1834. — The  type  of  the  species,  therefore  C.  vis- 
cidiflorus typicus. 

40.  LiNOSYRis  l.\nceolata  Torrey  and  Gray,  Fl.  N.  Am.  2:  233,  1842. — C.  viscidiflorus  lanceolatus. 

41.  L.  pumila  Gray,  PI.  Wright.  2:80,  1853. — C.  viscidiflorus  pumilus. 

42.  L.  serrulata  Torrey,  Stansbury  Rep.  ed.  1 :389,  1851. — The  form  of  this  as  originally  described  from 
specimens  from  the  Valley  of  Salt  Lake  differs  from  C.  viscidiflorus  typicus  only  in  the  scabrid  or  stiffly  short- 
ciliate  leaf-margins.  There  are  numerous  intermediate  forms  in  which  the  margins  vary  from  smooth  to 
strongly  scabrid,  so  that  it  becomes  impossible  to  draw  a  line  between  iypica  and  serrulata.  Moreover,  every 
glabrous  subspecies  includes  forms  with  scabrid-margined  leaves,  as  well  as  others  in  which  the  margins  are 
smooth.  Thus,  the  recognition  of  this  as  a  subspecific  character  would  necessitate  the  erection  of  at  least  5 
new  subspecies.  A  good  example  of  serrulata  is  Leiberg  8O4,  from  eastern  Oregon.  One  of  the  intermediate 
forms  is  Butler  1731,  from  Siskiyou  County,  California,  in  which  collection  the  leaves  are  mostly  scabrid  on  the 
margins,  but  only  minutely  so  and  for  only  a  portion  of  the  distance. 

43.  L.  viscidiflora  Torrey  and  Gray,  Fl.  N.  Am.  2:  234,  1842. — C.  viscidiflorus. 

44.  L.  viscidiflora  var.  latifolia  Eaton,  Bot.  King's  Expl.  157,  1871. — C.  viscidiflorus  latifolius. 

45.  L.  viscidiflora  var.  puberula  Eaton,  1.  c,  158,  1871. — C.  viscidiflorus  puberulus. 

46.  L.  viscidiflora  var.  serrulata  Torrey  in  Stansbury  Rep.,  ed.  2:389,  1853. — A  reduction  of  Linosyris 
serrulata,  which  see  in  this  list.  The  dates  here  given  for  the  two  editions  of  Stansbury's  Report  are  as  indi- 
cated by  CoviUe  (Bull.  Torr.  Club  23: 137,  1896). 

RELATIONSHIPS. 

The  only  species  to  which  C.  viscidiflorus  is  closely  related  is  C.  greenei,  but  there  can 
be  no  doubt  as  to  the  close  affinity  between  these  two.  The  reasons  for  considering 
them  as  distinct  are  stated  under  the  latter  species.  C.  vaseyi  has  been  frequently  com- 
pared with  varieties  of  viscidiflorus,  but  its  achenial  characters  indicate  that  the  connec- 
tion is  not  very  close,  as  has  been  already  pointed  out  (p.  180).  There  is  no  evidence  which 
permits  a  linking  of  viscidiflorus  with  any  species  of  the  other  sections  of  Chrysothamnus. 

Evolutionary  forces  have  been  operating  upon  C.  viscidiflorus  for  a  long  period  of  time, 
as  indicated  by  the  large  number  of  variations  that  have  been  produced.  However, 
judging  from  the  numerous  intergrades  that  are  constantly  being  found,  it  seems  just  as 
evident  that  the  resulting  variations  have  been  held  together  in  one  rather  close  major 
species,  perhaps  through  interbreeding  where  their  ranges  meet  or  overlap.  Absolute 
intergrading  is,  of  course,  almost  impossible  to  demonstrate  without  a  close  genetic 


C.    VISCIDIFLORUS.  187 

analysis,  but  the  nature  of  the  distinguishing  characters  is  such  that  it  is  believed  to  exist. 
At  any  rate,  the  constant  characters,  if  they  occur  at  all,  are  so  minute  and  unite  in  so 
perplexing  an  array  of  combinations  that  the  use  of  more  than  the  most  obvious  of  them 
in  taxonomic  studies  would  lead  only  to  hopeless  confusion.  One  notable  exception  to 
this  is  the  presence  or  absence  of  a  minute  but  dense  puberulence  on  the  upper  portions 
of  the  plants,  particularly  on  the  faces  of  the  upper  leaves  and  on  the  branches  of  the 
inflorescence.  When  this  is  present  at  all  it  is  usually  very  evident  and  in  two  cases  it 
occurs  in  subspecies  each  of  which  is  matched  almost  exactly,  except  for  this  character,  by 
another  of  a  similar  geographic  distribution.  These  two  pairs  of  subspecies  are:  steno- 
phyllus  (glabrous)  corresponding  to  puberulus  (puberulent),  and  pumilus  (glabrous)  cor- 
responding to  lanceolatus  (puberulent).  This  condition  is  very  suggestive  of  an  origin 
of  the  glabrous  varieties  through  mutation  from  their  respective  pubescent  counterparts, 
although  an  origin  through  gradual  variation  followed  by  isolation  and  a  subsequent 
reunion  geographically  after  the  characters  had  become  fixed  is  not  an  excluded  explana- 
tion. A  third  pair  of  forms  differing  only  by  this  same  character  is  indicated  by  a  col- 
lection of  typicus  made  by  Grinnell  6  km.  east  of  Jackass  Spring,  in  the  Panamint  Moun- 
tains of  eastern  California  (Univ.  Calif.  Herb.  201227).  In  this  collection  one  detached 
branch  is  perfectly  glabrous,  while  the  other  two,  which  match  the  first  in  every  other 
respect,  are  densely  puberulent  on  the  leaves  and  peduncles.  A  recurrence  of  this 
variation  is  found  in  a  collection  of  typicus  from  Mono  Lake,  California  {Bolander  6H2, 
in  part;  Univ.  Calif.  Herb.  31174  and  31175).  The  puberulence  here  referred  to  is  not 
to  be  confused  with  a  scabrid  or  subciliate  pubescence  which  often  occurs  on  the  margins 
of  the  leaves  and  is  quite  erratic  in  its  behavior.  Since  the  criteria  can  be  most  con- 
veniently discussed  under  the  subspecies  in  which  they  occur,  these  are  here  taken  up 
seriatim.  The  accompanying  diagram  (fig.  26)  has  been  prepared  as  an  aid  in  elucidating 
the  probable  relationships  between  the  various  subspecies,  which  discussion  can  best  be 
given  along  with  that  of  the  criteria. 

The  subspecies  lanceolatus  comes  the  nearest  of  all  to  representing  the'ancestral  type  of 
the  species.  This  conclusion  is  based  upon  the  assumption  that  the  green-leaved  forms 
preceded  the  pale-leaved  ones,  that  both  extremely  wide  and  extremely  narrow  leaves 
have  followed  as  modifications  from  medium-sized  leaves,  and  that  both  lack  of  pubes- 
cence and  thickening  of  the  bracts  are  derived  characters.  If  these  assumptions  are  cor- 
rect, then  lanceolatus  is  the  biologic  type  instead  of  typicus,  which,  however,  must 
still  be  retained  as  the  nomenclatorial  type.  The  connection  between  the  two  is  indicated 
by  occasional  specimens  having  all  the  characters  of  the  former,  except  that  they  are 
robust  and  tall  as  in  typicus  (Black  Canon,  Colorado,  Baker  685).  In  order  to  provide 
for  these  more  robust  plants  it  is  necessary  to  expand  somewhat  the  usual  conception  of 
lanceolatus  by  admitting  a  considerable  degree  of  variation  in  this  regard.  The  type 
specimens  give  no  clue  as  to  the  size  and  Nuttall's  original  characterization  of  "a  moder- 
ate-sized shrub  "  is  no  more  helpful.  In  the  above  citation  of  specimens  under  lanceolatus 
all  are  of  rather  low  stature,  mostly  under  4  dm.,  except  those  otherwise  indicated.  If 
the  tall  plants  really  are  distinct,  they  form  another  group  close  to  typicus,  but  differing 
in  the  close  although  minute  puberulence.  Experimental  evidence  is  here  much  needed. 
The  origin  of  the  other  subspecies  from  lanceolatus  has  not  proceeded  from  a  single  point. 
On  the  contrary,  it  seems  that  the  primitive  form  has  produced  others  through  variations 
in  several  directions.  One  of  these,  which  represents  the  end-point  of  one  series  of  varia- 
tions and  is  still  in  close  contact  with  lanceolatus  is  pumilus.  The  origin  of  this  from 
lanceolatus,  or  vice  versa,  by  mutation  has  been  already  suggested  (p.  187).  It  is  appar- 
ently much  less  common  than  this  and  occurs  farther  from  the  center  of  distribution  of 
the  species.  Both  of  these  facts,  as  well  as  its  glabrous  nature,  would  seem  to  indicate 
that  pumilus  is  the  derivative,  in  case  either  one  has  arisen  by  mutation  from  the  other. 


188 


GENUS   CHRYSOTHAMNUS. 


Taxonomically,  this  is  the  type  species  of  the  genus,  since  it  was  the  first  one  published 
by  Nuttall  under  his  new  genus,  Chrysothammis,  in  1841.  It  was  antedated,  however,  by 
Hooker's  Crinitaria  viscidiflora,  so  that  this  specific  name  takes  precedence  when  the  two 
are  united  into  one  major  species. 


Fio.  26. — Phylogenetic  chart  of  the  subspecies  of  Chrysoth 


viecidifioruB. 


The  next  group  centers  around  subspecies  puberulus,  through  which  they  are  connected 
with  lanceolatus.  All  are  characterized  by  a  peculiarly  pale,  usually  grayish  or  yellowish- 
green  herbage,  although  this  feature  is  not  sufficiently  constant  to  be  dependable  in 
taxonomic  work.  They  are  most  plentiful  in  the  Great  Basin  area.  Puberulus  has 
given  rise,  perhaps  by  mutation  as  already  noted,  to  the  glabrous  sienophyllus  and  by 
gradual  variation  to  humilis.  This  latter  is  a  reduced  far-western  type  of  high  altitudes. 
While  its  distinguishing  characters  do  not  seem  to  possess  much  taxonomic  value,  yet 
the  appearance  of  the  plants  is  so  unlike  that  it  seems  best  to  retain  the  form,  at  least 
provisionally,  as  a  distinct  subspecies. 


C.   VISCIDIFLORUS.  189 

The  subspecies  elegans  has  every  appearance  of  an  ecologic  derivative  of  lanceolatus, 
from  which  it  is  best  distinguished  by  its  narrower  leaves.  The  presence  of  the  thickened 
spot  on  the  bracts  is  not  always  easily  made  out,  since  it  varies  much  in  the  degree  of 
development.  It  recurs  elsewhere  in  the  species  only  in  linifolius,  but  it  does  not  indicate 
a  close  genetic  connection  between  these  two  subspecies,  as  is  shown  by  their  divergence 
in  other  characters.  On  the  contrary,  elegans  represents  a  closed  circle  in  that  it  has 
given  rise  to  no  other  variations  of  importance.  The  specimens  indicated  as  the  types 
at  the  Greene  Herbarium  are  mounted  on  two  sheets.  Unfortunately,  one  of  these 
(26610)  bears  also  a  piece  of  C.  vaseyi,  positively  identified  by  its  essentially  glabrous, 
elongated,  10-ribbed  achenes  and  also  by  the  non-tortuous  leaves.  This  specimen  is 
the  lower  middle  one  of  the  three  on  the  sheet.  The  other  two  have  achenes  and  foliage 
as  described  for  elegans  and,  together  with  the  other  sheet,  all  of  the  specimens  of  which 
are  genuine,  may  be  taken  as  the  types. 

As  is  so  often  the  case,  the  first  form  described  under  the  species  is  not  the  most 
primitive.  Therefore,  subspecies  typicus  is  represented  on  one  of  the  diverging  lines 
of  the  diagram.  The  type  specimen  is  not  now  accessible  to  us,  but  it  is  fairly  well 
defined  in  the  original  description,  which  in  full  is  as  follows : 

C.  viscidiflora ;  glaberrima,  foliis  lineari-laneeolatis  rigidis  integerrimis  acutissimis  uninerviis  basi  angustatis, 
floribus  fastigiato-corymbosis,  pedunculis  foliolosis,  involucri  glutinosi  cylindrici  5-flori  foliolis  imbricatis 
oblongis  exterioribus  minoribus  (Hooker,  Fl.  Bor.  Am.  2:24,  1834.). 

Hooker  then  refers  to  the  plant  as  a  common  shrub,  6  to  12  dm.  high,  and  in  comparing 
it  with  Chrysocoma  graveolens,  he  states  that  it  differs  in  the  leaves  being  only  single- 
nerved  and  the  branches  quite  glabrous,  not  in  the  least  pulverulently  tomentose.  This 
identifies  the  type  very  satisfactorily  with  a  common  form  of  the  Northwest,  except  that 
in  plants  which  correspond  in  every  other  way  the  leaves  are  usually  but  not  always 
3-nerved.  This  is  not  taken  as  a  matter  of  importance,  for  the  character  is  extremely 
variable  and  the  two  additional  nerves  are  often  so  faint  as  to  be  easily  overlooked. 
In  order  to  avoid  the  setting  up  of  a  new  subspecies,  it  is  necessary  also  to  include  in 
typicus  a  rare  form  with  narrowly  linear  instead  of  linear-lanceolate  leaves,  as  indicated 
by  minor  variation  38. 

Close  to  the  type  form,  but  differing  in  its  wider  leaves  with  a  larger  number  of  veins, 
is  subspecies  latif alius.  The  center  of  its  distribution  is  northeastern  Nevada,  whence 
comes  the  extreme  form  with  very  wide  elliptic  leaves.  The  smooth  green  foliage  and 
general  appearance  suggest  linifolius,  but  the  bracts  are  much  thinner  and  the  plants 
probably  are  not  alkali-tolerant.     It  is  more  likely  a  direct  offshoot  from  typicus. 

The  robust  habit,  large,  thick  leaves,  and  thickened  spot  on  the  bracts  render  linifolius 
the  most  striking  of  all  the  subspecies  when  it  occurs  in  its  extreme  development.  But 
in  all  of  these  characters,  which  are  doubtless  the  result  of  its  strongly  alkaline  habitat, 
it  intergrades  into  typicus  and  latifolius.  This  may  be  noted  in  the  vicinity  of  Point 
of  Rocks,  Wyoming.  Here  the  plants  growing  on  alkaline  soil  have  all  of  the  characters 
of  linifolius,  while  by  selecting  areas  where  the  alkali  is  less  abundant,  such  as  those 
lying  to  the  west,  all  gradations  in  the  characters  may  be  noted  until  the  plants  are  in 
no  way  distinguishable  from  typicus. 

ECOLOGY. 
The  low  forms  of  Chrysothamnus  viscidiflorus  constitute  typical  societies  in  the  south- 
western portions  of  the  mixed  prairie  and  throughout  the  sagebrush  association  of  the 
Great  Basin,  while  the  taller  ones,  such  as  typicus,  are  rather  to  be  regarded  as  consocia- 
tions of  the  sagebrush.  The  former  are  also  abundant  in  cedar  savannah.  Pumilus, 
lanceolatus,  and  serrulatus  are  the  common  subspecies  of  the  mixed  prairie,  and  often 
become  controlling  as  a  result  of  overgrazing.     In  this  respect  they  closely  resemble 


190  GENUS   CHRTSOTHAMNUS. 

Gutierrezia,  with  which  they  are  often  associated.  Pumilus  is  also  very  common  in 
sagebrush  areas,  and  is  often  dominant  in  bleared  areas.  Puberulus  and  stenophyllus 
are  chiefly  found  in  the  sagebrush  association,  especially  on  the  poorer  soils  and  in  dis- 
turbed areas. 

Linifolius  is  the  only  subspecies  to  grow  regularly  in  strongly  alkaline  soil,  even  being 
associated  on  alkali  flats  and  creek  bottoms  with  Sarcobatus.  However,  pumilus  is 
frequently  found  with  such  halophytes  as  Atriplex  confertifolia  and  A.  nuttalli,  and 
stenophyllus  may  occur  with  A.  confertifolia,  Sporobolus  airoides,  and  others. 

USES. 

All  of  the  variations  of  C.  viscidiflorus  are  browsed  to  a  limited  extent  by  sheep  and 
perhaps  also  by  cattle.  Some  stockmen  report  the  plants  as  of  no  value,  but  this  applies 
only  to  districts  where  other  feed  is  fairly  plentiful.  Throughout  the  Great  Basin, 
and  especially  from  Inyo  County,  California,  to  eastern  Washington,  the  shrubs  furnish 
good  sheep-feed,  the  animals  relishing  especially  the  flowering  shoots.  Three  of  the 
subspecies  have  been  examined  for  rubber  with  negative  results.  In  linifolius,  however, 
rubber  was  found  to  be  present  to  the  extent  of  1  per  cent  of  the  dry  weight.  This  is  not 
sufficient  to  be  of  more  than  passing  interest.  It  is  perhaps  correlated  with  the  alkaline 
habitat,  since  in  C.  nauseosus  it  is  found  that  the  highest  rubber-content  occurs  in  those 
forms  which  inhabit  alkaline  soils.  If  this  is  a  law  of  general  application  in  the  genus, 
then  the  other  subspecies  of  C.  viscidiflorus  could  not  be  expected  to  yield  rubber,  since 
none  of  them  grows  in  alkaline  situations. 

6.  CHRYSOTHAMNUS  GREENEI  (Gray)  Greene,  Erythea  3:94,  1895.    Plate  28. 

Shrub  1  to  3  dm.  high,  bushy,  much  branched  from  the  base;  bark  of  basal  portion 
brown,  fibrous,  peeling  off  in  sheets;  twigs  very  brittle,  erect  and  congested,  glabrous, 
at  first  green  but  soon  white  and  shining;  leaves  narrowly  linear  or  nearly  filiform, 
pungently  acute,  1  to  3.5  cm.  long,  0.3  to  1.2  mm.  wide,  1-nerved,  rigid,  either  nearly 
glabrous  or  only  sparsely  and  minutely  scabrous-ciliate,  more  or  less  viscidulous;  heads  in 
terminal  rounded  or  flat-topped  cymes;  involucre  5  to  7  mm.  high;  bracts  15  to  20,  in 
5  poorly  defined  vertical  ranks,  oblong,  abruptly  narrowed  to  a  subulate  tip  or  the  outer 
ones  more  gradually  attenuate,  glabrous  but  viscidulous;  flowers  5;  corolla  (whitish  or 
yellow)  tubular-funnelform,  the  throat  abruptly  dilated,  4  to  4.5  mm.  long,  glabrous; 
lobes  lanceolate,  0.8  to  1.3  mm.  long,  spreading,  glabrous;  anther-tips  lanceolate,  acute, 
about  0.5  mm.  long;  style-branches  exserted,  the  appendage  much  shorter  than  the 
stigmatic  portion;  achenes  nearly  prismatic,  about  3  mm.  long  when  mature,  densely 
appressed-villous;  pappus  rather  scant  and  rigid,  scarcely  equaling  the  corolla,  dull  white. 
{Bigelovia  greenei  Gray,  Proc.  Am.  Acad.  11 :75,  1876.) 

Plains  and  low  hills  from  southern  Colorado  to  New  Mexico,  Arizona,  Nevada,  and 
Utah. 

SUBSPECIES. 

C.  greenei  exhibits  a  tendency  to  break  up  into  two  divergent  groups  of  forms,  as 
follows : 

Key  to  the  Subspecies  of  Chrj/sothamnus  greenei. 

Leaves  mostly  2.5  to  3.5  cm.  long,  1  mm.  or  more  wide (a)  typicus  (p.  190). 

Leaves  mostly  less  than  2  cm.  long,  less  than  1  mm.  wide (b)  filifolius  (p.  191). 

6a.  Chrysothamnus  greenei  typicus. — Plant  low  and  stout;  leaves  narrowly  linear, 
usually  2  to  3.5  cm.  long  and  about  1  mm.  wide,  usually  dark  green;  heads  in  loose  cymes, 
mostly  on  distinct  peduncles;  involucre  5.2  to  7.0  mm.  high,  2  to  3  mm.  broad.  (C. 
greenei  Gray,  Proc.  Am.  Acad.  11:75,  1876.)  Southern  Colorado,  Utah,  and  eastern 
Nevada.  Type  locality,  Huerfano  Plains,  southern  part  of  Colorado.  Collections 
(these  are  cited  in  table  19). 


C.    GREENEI.  191 

66.  Chrysothamnus  greenei  filifolius  (Rydberg). — Plant  often  taller  and  more 
slender,  bushy;  leaves  linear-filiform,  usually  1  to  2  cm.  long  and  less  than  1  mm.  wide, 
often  pale  green;  heads  in  compact  cymes,  sessile  or  subsessile;  involucre  5  to  6  mm. 
high,  2  mm.  broad.  (C.  filifolius  Rydberg,  Bull.  Torr.  Club  28:503,  1901.)  Range  of 
the  species.  Type  locality,  Granite,  Colorado.  Collections:  Black  Rock,  New  Mexico, 
July  23,  1906,  Wooton  (US);  Navajo  Indian  Reservation,  Arizona,  Standley  7365  (US). 
(Additional  collections  are  indicated  in  table  19.) 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  BiGELOViA  QREENEi  Gray,  Proc.  Am.  Acad.  11:75,  1876. — C.  greenei  typicus. 

2.  Chrysothamnus  filifolius  Rydberg,  Bull.  Terr.  Club  28:503,  1901.— C.  greenei  filifolius. 

3.  C.  LARiciNUs  Greene,  Pittonia  5:110,  1903. — This  appears  to  be  C.  greenei  and  probably  subspecies  ^Zi- 
f alius.     The  type  specimen  can  not  be  found  at  present. 

4.  C.  PUMILUS  var.  acuminatus  Nelson,  Bot.  Gaz.  28:376,  1899. — C.  greenei  typicus.  Type  locality,  La 
Veta,  Colorado. 

5.  C.  scoPARius  Rydberg,  I.e.,  504. — C.  greenei  typicus.  Reduced  by  Rydberg  (Fl.  Rocky  Mts.  856,  1917). 
Type  locality,  mesas,  La  Veta,  Colorado. 

RELATIONSHIPS. 

In  Gray's  synopsis  this  species  was  placed  next  to  ceruminosus  on  the  strength  of  the 
similarly  tipped  involucral  bracts.  This  single  similarity  can  not  outweigh  all  of  the 
other  evidence,  such  as  the  strongly  pannose  flexuous  twigs  and  strongly  keeled  bracts  of 
ceruminosus,  which  plainly  assign  this  latter  to  subspecies  rank  under  C.  nauseosus.  C. 
greenei,  on  the  other  hand,  is  of  close  affinity  with  C.  visddiflorus,  and  the  specimens  in 
herbaria  are  often  ticketed  as  one  of  the  varieties  of  that  polymorphous  species,  usually 
as  variety  stenophyllus.  In  common  with  these  it  has  the  low  bushy  habit,  stifT  very 
brittle  white-barked  stems,  similar  involucres,  and  comparatively  short  style-append- 
ages. It  is  probable  that  its  similarity  to  stenophyllus  is  more  than  superficial  and 
indicates  a  close  genetic  relationship.  However,  it  is  well  separated  on  the  strength 
of  its  attenuate  or  abruptly  tipped  involucral  bracts  and  of  the  comparatively  sharp 
distinction  between  the  tube  and  throat  of  the  corolla.  Furthermore,  the  style-appen- 
dages in  greenei  are  shorter  in  proportion  to  the  length  of  the  stigmatic  portion  than  in  all 
but  an  occasional  example  of  any  subspecies  of  visddiflorus.  In  this  respect  it  resembles 
C.  vaseyi,  as  will  be  further  discussed  under  that  species. 

The  division  of  greenei  into  two  subspecies  is  here  given  with  some  question  as  to  its 
value,  but  it  follows  the  tendency  of  recent  writers  to  give  filifolius  specific  rank.  The 
first  of  these  was  Rydberg,  who  distinguished  the  segregates  only  on  size  of  leaf  and 
heads  and  on  the  color  of  the  former.  This  was  done  in  distinguishing  his  new  filifolius 
from  scoparius  (Bull.  Torr.  Club  28:503,  1901),  the  latter  since  reduced  by  Rydberg  to 
greenei  (Fl.  Rocky  Mts.  856,  1917).  The  gradation  in  these  characters  is  indicated  in 
table  19,  in  which  the  length  of  the  longest  leaves,  average  width  of  mature  middle  leaves, 
and  the  average  height  of  fully  developed  involucres  is  given. 

From  table  19,  which  includes  all  of  the  available  material,  it  is  seen  that  the  speci- 
mens may  be  divided  into  two  groups  based  upon  size  of  leaf  and  that  the  group  with  the 
smaller  leaves  inhabits  chiefly  Utah  and  Nevada,  a  more  arid  region  than  Colorado, 
whence  come  most  of  the  collections  of  the  larger-leaved  group.  The  size  of  the  involucre 
is  seen  to  vary  irrespective  of  the  leaves,  although  there  is  a  tendency  toward  reduced 
involucres  in  filifolius.  Rydberg  described  typicus  (under  the  synonym  scoparius)  as  of 
lighter  color  than  the  other,  but  the  tendency  is  the  other  way,  that  is,  the  paler  plants 
usually  belong  to  the  more  westerly  filifolius.  This  is  in  keeping  with  the  usual  reduction 
in  chlorophyll  as  a  species  passes  into  the  more  arid  Great  Basin  area. 

Additional  characters  have  been  introduced  by  Wooton  and  Standley  (Contr.  U.  S. 
Nat.  Herb.  19:661,  1915).     They  assign  short-pedunculate  or  sessile  heads  subtended  by 


192 


GENUS   CHRYSOTHAMNUS. 


long  bracts  to  filifoUus.  This  is  useful  in  that  it  calls  attention  to  the  fact  that  this 
narrow-leaved,  small-headed  form  has  a  more  compact  inflorescence  than  typicus. 
However,  the  individual  heads  in  the  latter  are  also  sometimes  sessile  (for  example, 
Purpus,  6264),  while  the  variation  in  the  length  of  the  subtending  bracts  does  not  vary- 
in  unison  with  other  characters.  Since  the  two  forms  occupy  the  same  general  terri- 
tory, careful  field  observations  should  be  made  to  see  if  they  are  not  entirely  ecologic 
in  their  origin. 

Table  19. — Vartation  in  the  subspecies  of  Chrysothamnus  greenei. 


Ratio  of  length 
of  style-append- 
age to  total 
branch. 

Leaves. 

Height 
of  invo- 
lucre. 

Her- 
barium. 

Length. 

Width. 

Subspecies  typicus: 

Gr. 
Gr. 
CI 

NY 
R 
UC 
NY 
UC 

NY 
UC 
UC 
UC 
Gr. 

per  cent. 

4o!o 
40.0 
30.0 
33.0 

36.4 

31.6 
30.0 
36.1 

3.5 
3.2 
2.5 
3,3 
3.0 
3.5 
2.5 
2.8 

2.3 
2.0 
1.8 
1.8 
1.2 

1.0 

}? 
1^2 
1.0 

i!o 

0,9 

0.3 
1.0 
0,5 
0.6 
0.4 

5.8 
6.0 
5.2 
6.5 
5.5 
5.2 
7,0 
6,0 

5,7 
5,5 
4,8 
6,0 
5,0 

La  Veta   Colo     Vreeland  698^ 

Southwestern  Utah   Rydberg  and  Garrett  9677 

Subspecies  filifoUus: 

Granite   Colo     Clements  S90' 

Thurber    Utah   Jones  5706 

Pancake  Range    Nev     Purpus  6397 

'  Type  of  Chrysothamnus  greenei  Gray, 

'  Type  of  C.  acoparius  Rydberg,  minor  variation  5. 


'  Type  of  C.  pumilus  acumiTmtus  Nelson,  minor  variation  4. 
'  Type  of  C.  filifoUus  Rydberg  =  C.  greenei  filifoUus. 


ECOLOGY  AND  USES. 

Chrysothamnus  greenei  is  a  low  shrub,  blooming  during  August  and  September.     It 

forms  a  climax  society  in  mixed  prairie  in  the  San  Luis  Valley,  Colorado,  while  in  Utah 

it  sometimes  forms  a  subclimax  consocies  on  sandy  alkaline  plains.    It  is  greatly  increased 

by  overgrazing,  and  hence  is  frequently  associated  with  Bouteloua  gracilis  in  short- 


There  is  no  specific  information  at  hand  regarding  the  value  of  this  plant.    As  a  browse 
shrub  it  is  probably  of  about  the  same  value  as  the  smaller  subspecies  of  C.  tnscidiflorus. 

7.  CHRYSOTHAMNUS  ALBIDUS  (Jones)  Greene,  Erythea  3 :  107,  1895.  Plate  28. 
Shrub  3  to  10  dm.  high,  fastigiately  branched;  twigs  brittle,  erect,  congested,  very 
leafy,  glabrous  but  very  resinous-viscid,  imparting  a  resinous  stain  to  paper,  at  first 
green  and  striate,  later  with  a  white  smoother  bark;  leaves  flat  and  1  to  2  mm.  wide 
but  drying  to  filiform  through  revolution  of  the  margins,  pungently  acute,  2  to  4  cm. 
long,  1 -nerved,  moderately  rigid,  glabrous  but  with  a  copious  resinous  exudate,  the 
surface  with  small  pits ;  heads  in  small  congested  cymes  which  are  either  simple  or  them- 
selves loosely  cymose;  involucre  7  to  9  mm.  high;  bracts  about  15,  in  very  obscure 
ranks,  lance-oblong,  all  but  the  innermost  abruptly  narrowed  to  a  long  setiform  usually 
curved  tip,  glabrous,  glutinous,  the  thin  margins  somewhat  erose,  the  tip  sometimes 
herbaceous;  flowers  5  to  6  (whitish  or  at  least  pale  yellow);  corolla  with  slender  tube 
and  abruptly  dilated  short  throat,  7  to  8  mm.  long,  glabrous;  lobes  linear,  acute,  2 
to  2.5  mm.  long,  erect;  anther-tips  triangular,  obtusish,  0.2  mm.  or  less  long;  style- 
branches  exserted,  the  slender  appendage  (about  2  mm.  long)  much  exceeding  the  short 
stigmatic  portion  (0.5  to  1.0  mm.  long);  achenes  tapering  to  the  base,  about  4  mm.  long, 


C.   ALBIDUS C.   PULCHELLUS.  193 

when  fully  mature,   densely  villous;  pappus  copious,   exceeding  the  corolla,   white. 
(Bigelovia  albida  Jones  in  Gray,  Proc.  Ann.  Acad.  17:209,  1882.) 

A  plant  of  the  Great  Basin;  common  only  along  the  westerly  side  of  the  Salt  Lake 
Desert;  Utah  (Wendover  to  Fish  Springs  and  west,  according  to  Jones),  Nevada,  and 
eastern  middle  California.  Type  locality,  in  alkaline  soil,  Wells,  Nevada.  Collections: 
Willow  Springs,  Utah,  May  28  and  July  29,  1891,  A.  J.  Jones  (Mo.  Bot.  Card.);  Kelton, 
north  end  of  Great  Salt  Lake,  Utah,  Wetmore  466  (US) ;  Twin  Springs,  Nevada,  Purpus 
63S8  (NY,  UC,  US);  type  collection,  August  9,  1881,  M.  E.  Jones  (Herb.  Jones,  DS, 
Gr,  NY,  UC,  US);  same  locality.  Hall  11234  (UC);  saline  plains  of  Humboldt  County, 
Nevada,  1865,  Torrey  218  (NY);  Candelaria,  western  Nevada,  Shockley  (DS,  NY); 
Soda  Springs  and  Fish  Lake  Valley,  Esmeralda  County,  western  Nevada,  Shockley  554 
(Gr,  NY,  US);  Owens  Valley,  eastern  California,  1875,  Kellogg  (Gr). 

RELATIONSHIPS. 

This  species  is  remarkably  distinct  from  all  others.  The  setaceous  tips  to  the 
involucral  bracts  early  suggested  an  affinity  with  C.  parryi  and  the  resin-dots  are  very 
much  like  those  of  the  Punctati,  but  the  decidedly  cymose  inflorescence,  the  absence  of 
tomentum,  and  several  minor  characters  indicate  that  the  connection  with  these  is 
not  very  close.  It  seems  to  stand  phylogenetically  between  parryi  and  the  Typici, 
approaching  the  latter  perhaps  through  C.  greenei,  with  which  it  has  much  in  common. 
It  need  not  be  confused  with  this  latter  species,  however,  for  it  is  a  more  robust  plant 
with  glutinous  foliage  and  larger  heads  of  a  distinct  aspect.  The  tips  to  the  bracts  are 
longer  and  much  more  curved  than  in  greenei,  the  flowers  are  nearly  white  instead  of 
yellow,  and  the  corolla  is  fully  2  mm.  longer.  C.  albidus  differs  from  all  other  species  of 
Chrysothamnus  in  the  remarkably  short  anther-tips,  and  in  no  other  is  the  stigmatic 
portion  of  the  style-branch  so  short  in  proportion  to  the  appendage.  It  is  this  last 
character  especially  that  renders  the  species  anomalous  among  the  Typici  and  suggests 
that  it  should  perhaps  be  set  off  in  a  section  by  itself.  The  impressed  resin-dots  are 
suggestive  of  those  so  highly  developed  in  the  section  Punctati,  but  there  is  no  evidence 
of  a  direct  phylogenetic  connection  with  this  group. 

Judging  only  from  the  rather  scant  material  thus  far  collected,  C.  albidus  is  not  given 
to  much  variation.    No  segregate  species  or  varieties  have  been  proposed. 

ECOLOGY  AND  USES. 
Chrysothamnus  albidus  is  a  pronounced  halophyte,  as  indicated  by  its  thickish  narrow 
leaves  with  revolute  margins  and  resin-dots.     In  strongly  alkaline  flats  it  mixes  with 
C.  n.  consimilis,  Elymus  condensatus,  and  Sarcobatus,  but  it  also  invades  even  more 
alkaline  areas  as  a  pioneer  family.     Its  scarcity  precludes  commercial  use. 

Section  III.    PULCHELLI. 
8.  CHRYSOTHAMNUS  PULCHELLUS  (Gray)  Greene,  Erythea  3:107,  1895.    Plate  29. 

Shrub  3  to  10  dm.  high,  densely  branched  at  the  base;  bark  of  old  stems  gray  or  brown; 
twigs  very  brittle,  short  and  divergent,  leafy,  glabrous,  striate,  the  bark  at  first  greenish 
but  soon  becoming  gray  or  white;  leaves  revolute-filiform  to  linear-oblong,  mucronate, 
1  to  4  cm.  long,  0.5  to  2  mm.  wide,  1-nerved,  green,  glabrous  or  the  margins  and  midrib 
ciliolate-scabrous  (whole  surface  finely  puberulous  in  one  variety);  heads  several  to 
numerous  in  each  terminal  usually  lax  cyme;  involucre  10  to  13  mm.  high;  bracts  20, 
25,  or  30,  in  5  sharply  defined  vertical  ranks,  boat-shaped,  strongly  keeled,  attenuate, 
rigid-chartaceous,  more  or  less  greenish  toward  the  apex,  glabrous;  flowers  usually  5; 
corolla  tubular-funnelform,  the  very  slender  tube  passing  gradually  into  the  throat, 
about  10  to  14  mm.  long,  glabrous  or  only  granular  on  the  surface;  lobes  1.5  to  2  mm. 


194  GENUS   CHRYSOTHAMNUS. 

long,  lanceolate,  nearly  erect,  glabrous;  anther-tips  lanceolate,  acute,  about  0.6  mm. 
long;  style-branches  long-exserted,  the  slender  appendage  about  the  length  of  the  stig- 
matic  portion,  achenes  nearly  prismatic,  4-angled,  and  with  strong  vertical  ribs  between 
the  angles,  6  to  7  mm.  long,  smooth  and  glabrous  to  minutely  but  densely  puburulent 
(various  degrees  on  the  same  plant) ;  pappus  exceeding  the  corolla,  fine  and  soft,  tawny. 
{Linosyris  pulchella  Gray,  PI.  Wright.  1 :96,  1852;  Torrey,  Sitgreaves  Rep.,  plate  4,  1853.) 
Southern  Rocky  Mountains  and  western  Kansas  south  into  Mexico;  southern  Colorado, 
Kansas,  New  Mexico,  western  Texas,  northern  Chihuahua,  Utah. 

SUBSPECIES. 
Chiefly  because  of  the  small  amount  of  field  work  that  has  been  given  to  this  species, 
its  forms  and  their  relationships  to  one  another  are  not  well  understood.    Three  species 
have  been  described  and  are  here  taken  as  subspecies,  as  follows: 

Key  to  the  Sxibspedes  of  Chrysothamnus  pulchellua. 
Leaves  glabrous  on  the  faces;  shrub  low. 

Margins  of  the  leaves  glabrous (a)  typieus  (p.  194). 

Margins  of  the  leaves  scabrous-ciliolate (6)   baileyi  (p.  194) . 

Leaves  finely  and  densely  puberulous  on  both  faces;  shrub  tall (c)   elatior  (p.  194). 

8a.  Chrysothamnus  pulchellus  typicus. — Shrub  low,  probably  under  5  dm.  high, 
openly  branched;  leaves  filiform  to  narrowly  linear,  perfectly  glabrous;  peduncles 
glabrous;  involucre  10  to  13  mm.  or  less  high;  bracts  gradually  acuminate.  {Linosyris  pul- 
chellus Gray,  1.  c).  Throughout  the  range  of  the  species,  except  easterly.  Type  locality, 
prairies  below  El  Paso  (western  Texas),  according  to  Gray  (PI.  Wright.  2:80,  1853). 
Collections:  Type  collection,  October,  1849,  Wright  287  (Gr,  US);  White  Sands,  Otero 
County,  New  Mexico,  Wooton  2501  (US) ;  north  of  Deming,  New  Mexico,  Goldman  1505 
(US);  Colonia  Diaz,  Chihuahua,  Nelson  6454  (Gr). 

Sb.  Chrysothamnus  pulchellus  baileyi  (Wooton  and  Standley). — Shrub  low, 
probably  under  5  dm.  high,  densely  branched;  leaves  linear  or  linear-oblong,  minutely 
ciliolate  with  short  stout  hairs,  otherwise  glabrous;  peduncles  glabrous ;  involucre  10  to  12 
mm.  high;  bracts  abruptly  acuminate,  mostly  bristle-pointed.  (C.  baileyi  Wooton 
and  Standley,  Contr.  U.  S.  Nat.  Herb.  16: 181,  1913.)  Kansas  to  New  Mexico  and  Texas. 
Type  locality,  north  end  of  the  Guadalupe  Mountains,  New  Mexico.  Collections: 
Kearney  County,  Kansas,  1897,  Hitchcock  (Gr,  NY,  US);  dunes  south  of  Mustang 
Spring,  Texas,  September,  1881,  Havard  (NY,  US);  type  collection,  September  4,  1902, 
Vernon  Bailey  490  (US);  bad  lands  at  Ojo  Alamo,  northwestern  New  Mexico,  Hall 
111S3  (UC);  White  Mountains,  Lincoln  County,  New  Mexico,  Wooton  508  (NY,  US). 

8c.  Chrysothamnus  pulchellus  elatior  (Standley). — Shrub  tall,  about  7.5  to  10 
dm.  high,  slender;  leaves  linear,  finely  and  densely  puberulous  on  both  faces;  peduncles 
puberulous;  involucre  9  to  12  mm.  high;  bracts  abruptly  acuminate.  (C  elatior  Standley, 
Proc.  Biol.  Soc.  Wash.  26:118,  1913.)  Southern  New  Mexico.  Type  locality,  sandhills 
north  of  Goldenbergs,  San  Andreas  Mountains,  Dona  Ana  County,  New  Mexico.  Col- 
lection: Type  collection,  October  12,  1912,  E.  0.  Wooton  (US). 

SYNONYMS. 

The  synonymy  of  this  species  is  so  limited  that  it  is  all  included  in  the  above  text,  with  the  single  exception 
of  Bigelovia  pulchella  Gray  (Proc.  Am.  Acad.  8:643,  1873),  which  is  C.  pulchellus  typicus. 

RELATIONSHIPS. 
There  can  be  no  question  that  this  species  is  more  closely  related  to  C.  depressus  than 
to  any  other.    The  connection  between  them  and  their  relation  to  other  forms  will  be 
taken  up  under  that  species.     C.  bigelovi  also  has  been  associated  with  this  species, 


C.    DEPRESSUS. 


195 


first  by  Gray  (Pacif.  R.  R.  Rep.  4<:98,  1857)  and  later  in  all  manuals  in  which  it  was 
treated.  It  is  very  clear,  however,  that  the  two  are  not  closely  related  and  that  bigelovi 
is  a  subspecies  of  C.  nauseosus.  The  evidence  has  been  stated  in  a  previous  paper  (Hall, 
Univ.  Calif.  Publ.  Bot.  7:172,  1919). 

The  three  subspecies  are  much  closer  in  their  affinities  to  one  another  than  any  one 
of  them  is  to  depressus.  Their  differences  are  only  such  as  habit,  width  of  leaf,  and 
amount  of  pubescence.  Subspecies  baileyi  is  very  close  to  lypicus,  the  only  dependable 
difference  being  the  scabrid-ciliate  leaf  margins.  A  majority  of  the  specimens  in  herbaria 
under  pulchellus  have  this  character,  but  it  is  often  so  poorly  developed  as  to  be  over- 
looked, as,  for  example,  in  Havard's  Texan  collection  cited  above.  According  to 
Standley  (Proc.  Biol.  Soc.  Wash.  26:119,  1913),  elatior  differs  decidedly  in  habit  as  well 
as  in  pubescence,  and  further  field  studies  may  warrant  its  recognition  as  a  species. 
ECOLOGY  AND  USES. 

Chrysothamnus  pulchellus  is  an  undershrub,  which  occurs  sparsely  in  subclimax  areas 
with  C.  n.  bigelovi,  Muhlenbergia  pungens,  etc.,  and  persists  for  a  time  after  Bouteloua 
gracilis  becomes  dominant.    No  uses  are  known. 

Table  20. — Variation  in  Chrysothamnus  pulchellus. 


Herbarium. 

lucre- 
length. 

Corolla. 

Style. 

Length, 
includ- 
ing 
lobes. 

Lobe- 
length. 

Ratio  of 

lobe- 
length  to 
total 

length. 

Stig- 
matic 
portion, 
length. 

Append- 
age, 
length. 

Ratio  of 

append- 
age-length 

to  total 
length  of 

branch. 

Subspecies  typicus: 

Las  Palomas,  N.  Mex 

Deming,  N.  Mex 

Fort  Smith  to  Rio  Grande.  . . 

Diaz,  Chihuahua 

Canto  Recia,  Chihuahua.... 
Paso  del  Norte,  Chihuahua.  . 

NY 

499434  US 

US 

360170  US 

Gr 

87217  UC 

12.6 
12.0 

10.2 
11.0 

10.0 
12.4 
13.5 
14.1 
13.6 
13.3 

mm. 
1.7 
1.7 
1.4 
1.8 
2.1 
1.9 

p.ct. 
17.0 
13.8 
10.4 
12.8 
15.4 
14.3 

mm. 
2.3 
young 
3.0 
3.1 
3.8 
3.1 

2.0 
young 
2.7 
3.0 
2.8 
2.7 

.... 
46.5 

47.4 
49.2 
42.4 
46.5 

11.8 

12.8 

1.8 

13.9 

3.1 

2.6               46.4       1 

Subspecies  baileyi: 

Nara  Visa,  N.  Mex 

Ojo  Alamo   N   Mex 

564968  -US 
205843  UC 

11.0 
12.0 

13.5 
9.5 

1.3 
1.7 

9.6 
17.9 

4.0 
2.2 

3.2 

2.7 

44.4 
65.1 

Average 

11.5     1     11.5     1     1.5 

13.7       1        3.1       )       2.9       1       49.7       ] 

9.  CHRYSOTHAMNUS  DEPRESSUS  NuttaU,  Jour.  Phila.  Acad.  H,  1:171,  1847.    Plate  29. 

Shrub  or  undershrub,  1  to  3  dm.  high,  forming  dense  clumps,  irregularly  much 
branched,  the  lower  branches  decumbent;  bark  of  old  stems  gray  or  brown;  twigs  brittle, 
numerous,  short,  densely  cinerous  with  a  minute  scabrous  pubescence,  striate;  leaves 
oblanceolate  or  spatulate,  acute,  erect,  0.8  to  2  cm.  long,  1  to  4  mm.  wide,  1-nerved, 
rigid,  finely  puberulent  like  the  twigs;  heads  in  small  compact  terminal  cymes;  involucre 
9  to  12  mm.  high;  bracts  20  or  25,  in  5  sharply  defined  vertical  ranks,  boat-shaped, 
keeled,  attenuate  to  a  short  mucro  or  soft  awn,  commonly  brown  on  the  back,  minutely 
rough-puberulent  on  the  exposed  parts;  flowers  5;  corolla  tubular-funnelform,  the  tube 
passing  gradually  into  the  slightly  broader  throat,  7  to  9  mm.  long,  glabrous;  lobes 
lanceolate,  1  to  2.3  mm.  long,  nearly  erect,  glabrous;  anther-tips  lanceolate,  very  acute, 
about  0.5  mm.  long;  style-branches  exserted,  the  comparatively  thick  appendage  only 
slightly  exceeding  or  usually  shorter  than  the  stigmatic  portion;  achenes  nearly  pris- 


196 


GENUS   CHRYSOTHAMNUS. 


matic,  4-angled  to  rather  equally  8-ribbed,  tapering  slightly  to  the  base,  5  to  5.5  mm. 
long,  smooth  or  obscurely  pubescent  towards  the  summit;  pappus  slightly  longer  than 
the  corolla,  fine  and  soft,  brownish  tinged. 

Plains  and  lower  mountains  of  the  Southwest:  southern  Colorado  and  New  Mexico 
to  northern  Arizona,  Nevada,  and  Utah.  Type  locality,  "in  the  Sierra  of  Upper  Cali- 
fornia," as  stated  by  Nuttall,  but  the  type  specimen  is  labeled  Rocky  Mountains,  and 
the  species  is  not  known  from  California.  Collections:  Type  collection,  Nuttall  (Gr); 
Naturita,  southwestern  Colorado,  August  25,  1920,  Pay  son  (UC);  Sangre  de  Cristo, 
Colorado,  Parry  104  (Gr);  Cimarron,  Colorado,  September,  1890,  Jones  (Gr,  UC,  US); 
near  Dulce,  Rio  Arriba  County,  New  Mexico,  Standley  8087  (US) ;  San  Francisco  Moun- 
tains, Arizona,  October,  1884,  Lemmon  (UC) ;  Bright  Angel  Trail,  Grand  Canon,  Arizona, 
October  22,  1905,  Eastwood  (US);  Pioche,  southeastern  Nevada,  September  4,  1912, 
Jones  (UC);  Montezuma  Canon,  southeastern  Utah,  Rydberg  and  Garrett  9676  (NY, 
UC);  Marysvale,  Utah,  Jones  58^7  (NY,  UC,  US). 

SYNONYMS. 

1.  BiGELOViA  DEPRESSA  Gray,  Proc.  .\m.  Acad.  8:643,  1S73.     C.  depressus. 

2.  LiNOSTRis  DEPRESSA  Torrey  in  Sitgreaves  Rep.  161,  1854.     C.  depressus. 

RELATIONSHIPS. 

There  is  every  evidence  of  close  consanguinity  between  C.  depressus  and  C  pulchellus. 
The  two  are  connected  not  only  by  the  general  habit,  the  nature  of  the  woody  twigs, 
etc.,  but  by  the  similarly  shaped  corollas,  the  short  style-appendages  as  compared  with 
the  stigmatic  portion,  and  especially  by  the  numerous  strongly  keeled  Jaracts  which  are 
arranged  in  5  very  sharply  defined  rows.  While  there  is  a  general  tendency  to  vertical 
rows  in  the  involucres  of  all  of  the  species,  it  is  nowhere  so  pronounced  as  here.  The 
contact  between  these  two  species  is  suggested  by  C.  pulchellus  elatior,  in  which  the 
pubescence  is  very  similar  to  that  of  depressus.  On  the  other  hand,  the  characters 
separating  depressus  and  pulchellus,  although  not  marked,  are  sufficient  for  actual  species. 
The  leaf  of  the  former  is  of  the  oblanceolate  type,  that  is,  widest  above  the  middle, 
while  in  the  latter  the  leaves  are  always  linear;  the  corolla  in  depressus  is  only  about 
8  mm.  long,  in  pulchellus  it  is  10  to  14  mm.  long.  This  elongation  of  the  flowers  in 
pulchellus,  accompanied  as  it  is  by  a  longer  pappus,  gives  to  the  heads  a  very  charac- 

Table  21. — Variation  in  Chrysothamnus  depressus. 


Herbarium. 

Invo- 
lucre- 
length. 

Corolla. 

Style. 

Length, 
includ- 
ing 
lobes. 

Lobe- 
length. 

Ratio  of 

lobe- 
length  to 
total 
length. 

Stig-     1 

matic     1  Append- 
portion.          age, 
length.        length. 

1 

Ratio  of 

append- 
age-length 

to  total 
length  of 

branch. 

177034  UC 

us 

159551   UC 

US 

us 
us 

563115  us 
193513  UC 
205824  UC 

205818  UC 

205819  UC 
179479  UC 

10.2 
■i2;2' 

'l0'2' 
10.0 
9.0 
9.0 
9.0 

p.cU 
16.2 
20.9 
25.0 
16.3 
19.3 
25.0 
18.7 
21.2 
12.3 
23.9 
18.7 
19.4 

mm. 
2.3 
2.2 
2.0 
2.0 
3.0 
2.2 
2.5 
2.5 
2.2 
2.6 
1.8 
1.7 

mm. 
2.2 
1.7 
2.2 
2.1 
2.5 
2.0 
2.5 
1.7 
1.8 
2.6 
2.0 
1.8 

p.ct. 
48.9 
43.6 
52.4 
51.2 
45.4 
47.6 
50.0 
40.5 
45.0 
50.0 
52.6 
51.4 

91            19 

Marysvale   Utah 

8.0 
9.2 
8.8 
9.2 
9.1 
8.0 
8.1 
9.2 
8.0 
7.2 

2.0 
1.5 
1.7 
2.3 
1.7 
1.7 
1.0 
2.2 
1.5 
1.4 

Iron  County,  Utah 

Sandia  Mountains,  N.  Mei. .  .  . 
New  Mexico  (Standleu  8087).  . . 

Coconino,  Ariz 

San  Franciso  Mountains,  Ariz. . 
Do 

Pioche   Nev 

Average 

9.9 

8.5 

1.7 

19.7 

2.2 

2.1 

48.2 

C.    PYRAMIDATUS.  197 

teristic  appearance,  for  the  flowers  project  beyond  the  involucre  a  distance  equal  to  one- 
half  their  own  length,  the  pappus  thus  appearing  like  an  elongated  brush. 

In  describing  depressus,  Nuttall  stated  that  it  was  close  to  pumilus,  that  is  to  C. 
viscidiflorus  ■pumilus  of  this  monograph.  While  it  is  probably  closer  to  viscidiflorus  than 
to  any  other  species  outside  of  its  own  section,  its  connection  is  more  likely  to  be  through 
some  subspecies  of  the  pubescent-stemmed  series  and  probably  through  one  discovered 
since  Nuttall's  time.  It  is  almost  matched  in  habit  by  subspecies  humilis,  but  the  geo- 
graphic isolation  of  this  form  is  against  it  as  a  close  relative  of  depressus.  About  all  that 
can  be  said,  therefore,  is  that  pulchellus  and  depressus  are  intimately  associated  phylo- 
genetically  and  that  this  branch  is  probably  a  derivative  of,  or  has  given  rise  to  the 
viscidiflorus  group  of  subspecies,  presumably  through  some  form  close  to  humilis. 

ECOLOGY  AND  USES. 

Chrysothamnus  depressus  grows  sparsely  as  a  subclimax  undershrub  on  rocky  slopes, 
or  in  pockets  of  soil  on  cliffs.  It  also  persists  into  the  climax  stage,  where  it  occurs  with 
Bouteloua  gracilis. 

This  species  is  usually  found  to  be  closely  cropped,  apparently  by  sheep,  but  it  is  not 
sufficiently  abundant  to  be  of  much  importance  as  browse. 

Section  IV.     NAUSEOSI. 
10.  CHRYSOTHAMNUS  PYRAMIDATUS  (Robinson  and  Greenman).     Plate  30. 

Shrub  6  to  9  dm.  high,  the  branches  probably  ascending;  ultimate  twigs  widely  spread- 
ing, sparsely  leafy,  covered  with  a  close  white  tomentum,  this  deciduous  in  the  second 
year,  the  bark  then  brown;  leaves  more  or  less  fascicled,  narrowly  linear,  with  closely 
revolute  margins,  cuspidate,  0.5  to  3  cm.  long,  about  0.5  mm.  wide,  1-  or  2-nerved, 
green  and  viscidulous  above,  obscurely  tomentulose  to  white-woolly  beneath ;  heads 
numerous,  in  dense  leafy-bracted  lateral  spikes  which  are  assembled  into  terminal 
pyramidal  panicles;  involucre  6  to  7  mm.  high;  bracts  about  15,  the  ranks  obscure, 
1-nerved,  lanceolate,  the  margins  hyaline,  loosely  puberulent,  none  with  herbaceous  tips; 
flowers  5  to  10;  corolla  tubular-funnelform,  4  to  5  mm.  long,  the  tube  glabrous;  lobes 
about  1  mm.  long,  lanceolate,  recurved,  puberulent  at  tip;  anther-tips  lanceolate,  acute, 
about  0.3  mm.  long;  style-branches  long-exserted,  thick,  barely  acute,  the  appendage 
about  as  long  as  the  stigmatic  portion  (but  material  young  and  not  satisfactory) ;  achenes 
appressed- villous ;  pappus  about  equaling  the  corolla,  soft,  sordid  or  tawny.  {Bigelovia 
pyramidata  Robinson  and  Greenman,  Proc.  Am.  Acad.  32:43,  1896.) 

Mexico;  known  only  from  four  collections,  all  in  the  States  of  Oaxaca  and  Coahuila. 
Type  locality,  on  the  hills  above  Oaxaca,  altitude  1,700  m.  Collections:  Type  collection, 
November  16,  1894,  Pringle  6O48  (Gr,  UC,  US);  Canada  Sta.  Maria,  Oaxaca,  Seler  1477 
(Gr);  Monte  Alban,  near  Oaxaca  City,  Oaxaca,  between  1,700  and  1,850  m.  altitude, 
Smith  371  (US) ;  Sierras  de  Parras,  Coahuila,  in  rocky  soil,  Purpus  1326  (UC,  involucral 
bracts  scarcely  acute). 

RELATIONSHIPS. 

The  exact  position  of  C.  pyramidatus  in  the  genus  is  not  certain,  but  it  is  placed  in 
the  Nauseosi  because  of  the  pannose  tomentum  of  the  twigs.  The  decidedly  spicate  or 
subracemose  inflorescence  is  suggestive  of  a  remote  relationship  with  C.  parryi.  How- 
ever, there  is  no  tendency  toward  an  attenuation  of  the  tips  of  the  involucral  bracts 
and  the  style-tips  are  much  less  acute  than  in  parryi.  The  villous-puberulent  corolla- 
lobes  occur  elsewhere  in  Chrysothamnus  only  in  C.  parryi  latior  and  in  a  few  of  the  less 
specialized  subspecies  of  C.  nauseosus.  The  present  species  possibly  represents  a  primi- 
tive type  or  offshoot  from  the  main  line,  as  its  Mexican  habitat  also  suggests. 


198  GENUS   CHRYSOTHAMNUS. 

ECOLOGY  AND  USES. 
Chrysothamnus  pyramidatus  has  not  been  seen  in  the  field,  and  nothing  is  known  of 
its  ecology  and  uses. 

11.  CHRYSOTHAMNUS  PARRYI  (Gray)  Greene,  Erythea  3:113,  1895.     Plates  30  to  32. 

Shrub  6  dm.  or  less  high,  the  numerous  branches  erect  or  ascending,  or  widely  spread- 
ing in  dwarf  forms;  bark  of  main  stems  fibrous,  brown;  twigs  flexible,  ascending,  moder- 
ately leafy,  closely  covered  with  a  white  or  rarely  greenish  pannose  tomentum,  this 
deciduous  only  near  the  base,  the  bark  then  brown;  leaves  narrowly  to  broadly  linear 
or  linear-spatulate,  acute  or  at  least  mucronate,  1  to  8  cm.  long,  0.5  to  8  mm.  wide, 
1 -nerved,  sometimes  with  2  additional  nerves,  green  and  viscid-glandular  or  gray  and 
tomentulose;  heads  in  leafy  terminal  racemes,  these  sometimes  branching  and  sub- 
paniculate;  involucre  10  to  14  mm.  high;  bracts  10  to  20,  in  more  or  less  obvious  vertical 
ranks,  1 -nerved,  lanceolate,  acuminate,  chartaceous,  the  outer  ones  often  with  a  slender 
herbaceous  tip, loosely  puberulent  at  least  on  the  margins;  flowers  4  to  20;  corolla  tubular- 
funnelform,  8  to  11  mm.  long,  either  pubescent  or  glabrous;  lobes  0.5  to  2.5  mm.  long, 
erect,  glabrous  or  sparsely  long-hairy;  anther-tips  linear-lanceolate  and  acute  or  linear 
and  somewhat  obtuse  (at  least  in  subspecies  nevadensis) ,  0.5  to  0.8  mm.  long;  style- 
branches  long-exserted,  the  subulate  appendage  much  exceeding  the  stigmatic  portion; 
achenes  tapering  slightly  to  the  base,  4-angled,  5  to  6  mm.  long  when  mature,  densely 
appressed-villous;  pappus  equaling  or  slightly  exceeding  the  corolla,  very  soft,  dull 
white  changing  to  tawny.    {Linosyris  parryi  Gray,  Proc.  Acad.  Phila.  for  1863:66,  1863.) 

Mountains  and  foothills  of  western  North  America:  Wyoming  to  western  Nebraska, 
New  Mexico,  California,  and  Utah. 

SUBSPECIES. 

Key  to  the  Subspecies  oj  Chrysothamnus  parryi. 
Flowers  8  to  20  in  each  head,  or  only  5  to  7  in  latior  but  the  leaves  then  4  ram.  or  more 
wide;  leaves  lanceolate  or  oblanceolate  to  broadly  linear. 
Leaves  2.5  to  8  cm.  long;  plant  3  dm.  or  more  high,  the  branches  mostly  erect. 

Flowers  mostly  10  to  20  in  the  head;  leaves  mostly  L5  to  3  ram.  wide.     Rocky 

Mountains (a)  typicus  (p.  198). 

Flowers  mostly  5  to  11  in  the  head;  leaves  mostly  4  to  8  mm.  wide,  California. 

Involucre  9  to  10  ram.  high;  leaves  thick  and  rigid;  inflorescence  congested.  (6)  holanderi  (p.  199). 
Involucre  12  to  14  mm.  high;  leaves  thinner,  soft;  inflorescence  elongated. .   (c)   latior  (p.  199). 
Leaves  1.0  to  1.5  cm.  long;  plant  about  1  dm.  high,  the  branches  spreading  at  base. 

Southern  California (d)  imulus  (p.  200). 

Flowers  5  to  7  in  the  head,  or  up  to  10  in  asper  (the  leaves  then  resinous-scabrid) ;  leaves 
narrowly  linear  except  in  some  forms  of  asper. 
Bracts  of  the  involucre  8  to  12,  not  strongly  keeled  and  the  vertical  rows  rather 
obscure. 
Racemes  several-  to  many-headed;  foliage  green,  viscidulous,  not  tomentose  or 
only  sparsely  so. 

Resin-giands  of  the  leaves  short-stalked,  prominent (e)   asper  (p.  200). 

Resin-glands  of  the  leaves  se.ssile,  obscure (fj   vulcanicus  (p.  200). 

Racemes  reduced  to  1  or  2  heads  each;  foliage  gray,  tomentulose (g)  morwcephalus  (p.  200). 

Bracts  of  the  involucre  13  to  20,  rarely  only  11  or  12  (or  even  fewer  in  howardi, 
which    may    be    recognized    by  the    elongated  upper  leaves),   more 
strongly  keeled,  the  vertical  rows  fairly  obvious. 
Uppermost  leaves  elongated,  some  of  them  overtopping  the  inflorescence;  foliage 

gray-tomentulose;  flowers  pale  yellow.     Rocky  Mountains (h)  howardi  (p.  201). 

Uppermost    leaves   seldom    overtopping   the    inflorescence;    foliage    variously 
pubescent;  flowers  clear  yellow. 
Bracts  of  the  involucre  with  very  slender  straight  tips.     Rocky  Mountains,  (t)   atlenuatua  (p.  201). 
Bracts  of  the  involucre  with  slender  tips  at  least  some  of  which  are  spread- 
ing or  recurved.     Nevada  and  California (j)   nevadensis  (p.  201). 

11a.  Chrysothamnus  parryi  typicus. — Plant  3  dm.  or  more  high;  stems  mostly 
erect;  leaves  broadly  linear,  3  to  8  cm.  long,  1.5  to  3  mm.  wide,  3-nerved,  but  only  one 
nerve  prorninent,  green,  glabrous  or  microscopically  puberulent  and  often  obscurely  resin- 
ous-glandular, the  uppermost  usually  exceeding  the  inflorescence;  heads  numerous,  in 
dense  elongated  racemes;  involucre  9  to  12  mm.  high;  bracts  10  to  15,  obscurely  ranked, 


C.    PARRYI.  199 

not  strongly  keeled,  thin,  with  straight  attenuate  tips;  flowers  10  to  20.  {Ldnosyris 
parryi  Gray,  1.  c.)  On  dry  open  hillsides  and  plains,  Wyoming,  Colorado,  Utah,  and 
northeastern  Nevada.  Type  locality.  Rocky  Mountains,  latitude  39°  to  41°,  according 
to  label  on  type  specimen.  Collections:  Centennial-Rambler  Road,  Albany  County, 
Wyoming,  Goodding  2067  (Or,  R,  NY,  UC,  US);  type  collection,  1862,  Hall  and  Harbour 
293  (Gr);  Colorado:  Middle  Park,  1862,  Parry  (Gr,  US);  North  Fork,  Larimer  County, 
Goodding  1921  (DS,  Gr,  NY,  UC,  US);  mountains  about  headwaters  of  Clear  Creek, 
Patterson  222  (Gr,  NY,  UC) ;  Marshall  Pass,  3,000  m.  altitude.  Baker  878  (NY,  UC,  US) ; 
head  of  Sevier  River,  Utah,  Jones  6028  (NY,  UC,  US) ;  Big  Creek  and  Kingston  Canon, 
Toiyabe  Forest,  Nevada,  A.  E.  Hitchcock  830  (US). 

116.  Chrysothamnus  parryi  bolanderi  (Gray). — Plant  a  "low  shrub";  stems  erect, 
probably  from  a  much-branched  bushy  base;  leaves  3  to  4  cm.  long,  4  to  5  mm.  wide, 
many  3-nerved,  green,  somewhat  viscidulous,  the  uppermost  little  reduced  but  not  exceed- 
ing the  inflorescence;  heads  crowded  in  short  racemes  which  are  sometimes  branched,  the 
inflorescence  then  appearing  cymose;  involucre  9  to  10  mm.  high;  bracts  about  11  to  15, 
obscurely  ranked,  not  strongly  keeled,  thin,  with  straight  attenuate  tips;  flowers  8  to  11 
(or  as  low  as  7  according  to  Gray).  (Linosyris  bolanderi  Gray,  Proc.  Am.  Acad.  7:354, 
1868.)  Known  only  from  the  type  locality.  Type  locality,  Mono  Pass,  California,  at 
2,750  to  3,050  m.  altitude.  Collections:  Type  collection,  1866,  Bolander  6137  (Gr,  UC); 
same  locality,  1867,  Rattan  (DS,  in  part). 

lie.  Chrysothamnus  parryi  latior,  subsp.  nov. — Plant  about  4  dm.  high;  stems 
erect  or  ascending;  leaves  elliptic  or  oblanceolate,  acute,  mucronate,  tapering  to  a  narrow 
petiole-like  base,  2.5  to  4  cm.  long,  4  to  8  mm.  wide,  rigid,  1-nerved,  the  nerve  impressed 
above  but  prominent  beneath,  sometimes  an  additional  pair  of  nerves  from  base  of  leaf, 
but  these  soon  disappearing,  surface  dull  green,  sprinkled  with  microscopic  glandular 
dots,  also  obscurely  puberulent,  the  uppermost  much  shorter  than  the  inflorescence; 
heads  in  narrow  terminal  raceme-like  panicles,  interspersed  with  a  few  reduced  leaves 
(panicle  5  to  15  cm.  long);  involucre  cylindric-turbinate,  12  to  14  mm.  high;  bracts  11  to 
15,  in  5  indistinct  vertical  ranks,  1-nerved,  lanceolate,  attenuate  to  rigid  pungent  straight 
or  only  recurved-spreading  tips,  the  short  outer  ones  keeled,  all  chartaceous  and  nearly 
glabrous;  flowers  5  to  7,  corolla  tubular-funnelform,  11  mm.  long,  sparsely  puberulent 
on  the  tube;  lobes  about  2.5  mm.  long,  lanceolate,  erect  or  only  slightly  divergent,  sparsely 
villous  at  apex  in  the  bud;  anther-tips  lanceolate,  acute,  nearly  1  mm.  long;  style-branches 
about  5.5  mm.  long,  the  subulate  appendage  moderately  exceeding  the  stigmatic  portion; 
achenes  tapering  to  the  base,  4-angled,  densely  appressed- villous ;  pappus  slightly  exceed- 
ing the  corolla,  rather  soft,  tawny  to  ferruginous.  Known  only  from  the  mountains  of 
northern  California.  Collections:  Wagon  Creek,  at  the  foot  of  Mount  Eddy,  Siskiyou 
County,  California,  at  an  altitude  of  about  1,140  m.,  August  26,  1915,  A.  A.  Heller  12250 
(SF,  type,  duplicates  at  DS,  Gr,  UC);  same  locality,  August  30,  1912,  Eastwood  2079 
(SF,  UC) ;  Little  Hot  Springs  Valley,  Modoc  County,  August  18,  1899,  Baker  (UC) ;  in 
dry  brush  at  Sisson,  south  base  of  Mount  Shasta,  at  between  900  and  1,250  m.  altitude, 
September,  1902,  Grant  6152  (UC);  Mount  Shasta,  Canby  111  (Gr,  US). 

The  above  description  of  latior  was  drawn  from  the  type  specimen.  The  Eastwood 
specimen  is  in  close  agreement  and  may  indeed  have  been  taken  from  the  same  or  a 
neighboring  plant.  Its  flowers  are  older  and  the  villous  pubescence  of  the  corolla-lobes 
is  therefore  less  noticeable.  The  corollas  in  the  Baker  specimen  from  Modoc  County  are 
not  fully  opened.  The  corolla  and  its  parts  are  smaller  than  given  in  the  description, 
but  the  lobes  are  very  noticeably  villous.  Grant's  collection  from  Sisson  has  some  heads 
with  well-matured  achenes  and  some  with  flowers  only  in  bud.  These  latter  are  scarcely 
if  at  all  villous  on  the  lobes.     The  corollas  are  10  mm.  long  and  the  lobes  about  2  mm. 


200  GENUS   CHRYSOTHAMNUS. 

long.  This  collection  differs  from  all  of  the  others  in  its  somewhat  thinner  and  less  rigid 
leaves  and  nearly  glabrous  involucres.  It  is  probably  a  form  of  partially  shaded  places. 
According  to  the.  original  label,  the  plants  were  3  to  4.5  dm.  high.  The  range  of  C.  latior 
should  perhaps  be  extended  to  Mount  Hamilton,  on  the  basis  of  a  specimen  collected  in 
June,  1890,  by  Price  (Univ.  Calif.  Herb.  87224),  but  this  is  very  incomplete  and  there  is 
some  doubt  as  to  the  accuracy  of  the  data. 

lid.  Chrysothamnus  parryi  imulus,  subsp.  nov. — Plant  about  1  dm.  high;  stems 
spreading  at  base,  the  branches  erect ;  leaves  spatulate  or  linear-spatulate,  obtuse,  mucro- 
nate,  1  to  1.5  cm.  long,  2  to  3  mm.  wide,  1-nerved,  gray  with  a  dense  very  tardily  decidu- 
ous tomentum,  none  overtopping  the  inflorescence;  heads  few,  peduncled  in  a  reduced 
.raceme;  involucre  11  to  12  mm.  high;  bracts  about  16,  obscurely  ranked,  not  keeled,  thin, 
oblong,  pungently  and  rather  abruptly  acute,  the  outer  sometimes  with  herbaceous  red- 
dish tips,  white-tomentose;  flowers  11  to  15;  corolla  tubular-funnelform,  9  to  10  mni.  long, 
yellow  or  reddish,  the  tube  glabrous  or  obscurely  puberulent;  lobes  1  to  1.5  mm.  long, 
nearly  erect,  either  glabrous  or  sparsely  villous;  achenes  silky- villous ;  pappus  slightly 
exceeding  the  corolla.  Known  only  from  the  San  Bernardino  Mountains  of  southern 
California.  Collections:  Bear  Valley,  San  Bernardino  Mountains,  California,  at  2,000 
m.  altitude,  July  19,  1900,  M.  E.  Jones  (type,  in  Herb.  Jones);  same  locality,  1896, 
Davidson  (UC). 

lie.  Chrysothamnus  parryi  asper  (Greene). — Plant  1.5  dm.  or  more  high;  stems 
erect  or  slightly  spreading;  leaves  2  to  4  or  5  cm.  long,  1  to  3  mm.  wide,  1-nerved,  firm, 
green,  slightly  rough  with  numerous  short-stalked  resin-glands,  the  uppermost  leaves 
scarcely  equaling  the  inflorescence;  heads  few  in  the  short  racemes,  or  more  numerous 
and  the  racemes  longer  (12  cm.  in  the  type) ;  involucre  11  to  12  mm.  high;  bracts  9  to  13, 
somewhat  ranked,  thin,  with  straight  tips;  flowers  5  to  10.  (C  asper  Greene,  Leaflets 
1 :  80,  1904.)  On  mountains  bordering  the  desert,  western  Nevada  and  eastern  California. 
Type  locality,  Hockett  Trail,  in  the  valley  of  Little  Cottonwood  Creek,  eastern  slope  of 
the  Sierra  Nevada  of  Inyo  County,  California  (see  Coville,  Contr.  U.  S.  Nat.  Herb.  4:271, 
1893,  under  No.  1690).  Collections:  Bloody  Canon,  Mono  County,  California,  August 
13,  1898,  Congdon  (UC);  type  collection,  Coville  1690  (US);  Alamo  Mountain,  Ventura 
County,  California,  Hall  6701 ;  Lee  Canon,  Charleston  Mountains,  Nevada,  Heller  11036 
(DS,  Gr,  NY,  UC,  minor  variation  17). 

11/.  Chrysothamnus  parryi  vulcanicus  (Greene). — Plant  1.5  dm.  or  more  high; 
stems  erect  or  ascending;  leaves  2  to  5  cm.  long,  0.5  to  2  mm.  wide,  1-nerved  or  obscurely 
3-nerved,  green  and  minutely  resinous-glandular,  or  at  least  viscidulous,  the  uppermost 
scarcely  equaling  the  inflorescence;  heads  numerous,  in  elongated  often  lax  racemes  or 
narrow  panicles;  involucre  11  to  13  mm.  high;  bracts  9  to  12,  somewhat  ranked,  thin, 
with  straight  attenuate  tips;  flowers  5  to  7.  (C.  vulcanicus  Greene,  1.  c.)  In  the  southern 
Sierra  Nevada  Mountains  of  California.  Type  locality,  on  Volcano  Creek,  above  Vol- 
cano Falls,  at  about  2,500  m.  altitude.  Collections:  Type  collection,  August  9,  1904, 
Culbertson  4361  (Gr,  SF);  Golden  Trout  Creek  and  Ramshaw  Meadows,  Hall  84IS 
(UC,  US);  Little  Kern  River,  at  2,400  m.  altitude,  Hall  8457  (UC);  Mono  Mills,  in  sandy 
soil  beneath  Pinus  ponder osa,  Hall  10844  (SF,  UC). 

11^.  Chrysothamnus  parryi  monocephalus  (Nelson  and  Kennedy). — Plant  0.5  to  3 
dm.  high;  stems  rigidly  branched,  spreading;  leaves  1  to  3  cm.  long,  1.5  mm.  or  less  wide, 
1-nerved,  rarely  2-nerved,  gray,  sparsely  to  copiously  tomentulose,  also  viscidulous,  the 
uppermost  usually  exceeding  the  inflorescence;  heads  solitary  or  two  together,  terminal 
on  the  short  leafy  twigs;  involucre  10  to  11  mm.  high;  bracts  about  8  to  12,  the  ranks  very 
obscure,  thin,  tapering  to  a  straight  attenuate  apex;  flowers  5  or  6.     (C.  monocephalus 


C.    PARRYI.  201 

Nelson  and  Kennedy,  Proc.  Biol.  Soc.  Wash.  19:39,  1906.)  High  mountains  of  western 
Nevada  and  eastern  California.  Type  locality,  summit  of  Mount  Rose,  Washoe  County, 
Nevada.  Collections:  Type  collection,  from  3,320  m.  altitude,  Kennedy  1171  (UC); 
Mount  Rose,  Nevada,  at  3,170  m.  altitude.  Heller  9976  (Gr,  NY,  UC,  US);  mountains 
above  Lundy,  Mono  County,  California,  Minihorn  224  (UC) ;  outlet  of  Jessie  Lake,  east 
side  of  Mount  Dana,  California,  August  12,  1898,  Congdon  (UC) ;  Mono  Pass,  California, 
Bolander  61S5  (Gr,  with  notation,  "very  low  shrub"). 

llh.  Chrysothamnus  parryi  howardi  (Parry). — Plant  normally  3  to  6  dm.  high; 
stems  spreading  at  base,  but  the  branches  mostly  erect;  leaves  narrowly  linear,  2  to  4 
cm.  long,  about  1  mm.  wide,  commonly  with  straight  slender  tips,  1-nerved,  gray- 
tomentulose,  the  uppermost  usually  overtopping  the  inflorescence;  heads  either  numer- 
ous in  open  racemes  or  few  and  terminally  glomerate  in  reduced  forms  (minor  varia- 
tion 18) ;  involucre  10  to  12  or  13  mm.  high;  bracts  12  to  20,  in  rather  well  defined  ranks, 
keeled  by  the  strong  midrib,  with  usually  spreading  tips;  flowers  5  to  6,  rarely  7.  (Lino- 
syris  howardi  Parry  in  Gray,  Proc.  Am.  Acad.  6:541,  1865.)  On  upland  slopes  and 
tablelands,  Wyoming,  western  Nebraska,  and  Colorado;  perhaps  also  in  Utah.  Type 
locality,  Colorado,  on  gravelly  hills  near  "Hot  Springs"  of  Middle  Park.  Collections: 
Encampment,  Carbon  County,  Wyoming,  Goodding  2016  (Gr,  Ny,  UC,  minor  variation 
18);  Centennial-Rambler  Road,  Albany  County,  Wyoming,  Goodding  2072  (DS,  Gr,  NY, 
UC,  similar  variation);  canons  south  of  Scotts  Bluff,  Nebraska,  July  24,  1891,  Rydberg 
(NY,  US);  rolling  hills  north  of  Walsenberg,  Colorado,  Hall  10779;  Buena  Vista,  Colo- 
rado, Hall  11073  (UC);  Villa  Grove,  San  Luis  Valley,  Colorado,  Hall  10785  (UC). 

Hi.  Chrysothamnus  parryi  attenuatus  (Jones). — Plant  2  to  6  dm.  high;  stems 
mostly  erect;  leaves  narrowly  linear,  2  to  4  cm.  long,  about  1  mm.  wide,  1-nerved,  not 
tomentulose  but  green  and  somewhat  viscid,  the  upper  ones  not  projecting  beyond  the 
inflorescence  (in  the  type  specimens);  heads  in  well-developed  racemes;  involucre  10 
to  11.5  mm.  high;  bracts  13  to  15,  5-ranked,  keeled,  with  very  slender  usually  erect 
tips;  flowers  5  to  7.  (Bigelovia  howardi  var.  attenuata  Jones,  Proc.  Calif.  Acad.  II, 
5:691,  1895.)  Utah,  southern  Colorado,  northern  New  Mexico,  Arizona,  eastern 
Nevada,  and  southern  Idaho.  Type  locality,  Marysvale,  Utah,  at  2,150  meters  alti- 
tude, in  clay.  Collections:  Type  collection,  August  27,  1894,  Jones  6912  (NY,  UC, 
US) ;  same  locality,  Jones  5847a  (NY,  UC,  US) ;  Thurber,  Utah,  Jones  5704,  and  near 
Panguitch  Lake,  Utah,  Jones  6994  (both  UC,  US,  and  both  with  the  less  attenuate 
bracts  of  subspecies  howardi,  and  a  portion  of  5704  with  white  tomentum  of  minor  varia- 
tion 15,  C.  newberryi  Rydberg);  Wet  Mountain  Valley,  Fremont  County,  Colorado, 
Brandegee  748,  749  in  part  (UC,  a  form  with  the  bracts  less  attenuate);  Rio  Mancos, 
Colorado,  Brandegee  1231  (UC);  Canon  Largo,  New  Mexico,  September  15,  1859,  New- 
berry (NY,  type  of  C  newberryi  Rydberg,  minor  variation  15);  Buckskin  Mountains, 
northern  Arizona,  Jones  6052k  (US,  same  variation);  Star  Peak,  Nevada,  July  30,  1904, 
Jones  (DS,  UC,  same  variation) ;  Challis,  Custer  County,  Idaho,  Macbride  and  Payson 
3351  (R). 

11  j.  Chrysothamnus  parryi  nevadensis  (Gray). — Plant  2  to  6  dm.  high  except  in 
high-mountain  forms;  stems  erect  or  ascending;  leaves  1.5  to  4  cm.  long,  0.5  to  3  mm. 
wide,  1-nerved,  either  green  and  resinous-glandular  or  more  commonly  gray  and  copi- 
ously tomentulose  (the  two  forms  sometimes  growing  together;  see  minor  variation  20), 
the  uppermost  seldom  exceeding  the  inflorescence;  heads  few  to  numerous,  in  racemes 
or  narrow  panicles;  involucre  12  to  15  mm.  high;  bracts  13  to  18,  in  definite  ranks, 
strongly  keeled,  with  slender  tips  which  tend  to  recurve;  flowers  4  to  6.  (Linosyris 
howardi  var.  nevadensis  Gray,  Proc.  Am.  Acad.  6:541,  1865.)  Uplands  and  mountains 
nearly  to  timber  line,  eastern  Nevada  to  eastern  California  and  south  to  northern 


202  GENUS    CHRYSOTHAMNUS. 

Arizona.  Type  locality,  Mount  Davidson,  Nevada,  above  Virginia  City.  Collections: 
Type  collection,  Bloomer  (Or) ;  northwestern  Nevada,  Watson  570  (Gr) ;  Nevada :  Comet 
Peak,  Pioche,  August  30,  1912,  Jones  (UC);  near  Verdi,  July,  1888,  Sonne  (UC);  Frank- 
town,  Kennedy  1934  (DS,  Gr,  UC);  Kings  Canon,  Ormsby  County,  Baker  1503  (Gr, 
SF,  NY,  UC,  US);  Spanish  Springs  Valley,  Washoe  County,  Kennedy  1950  (DS,  Gr, 
NY,  UC,  US,  minor  variation  19);  Ebbett's  Pass,  California,  Breiver  1985  (Gr,  UC, 
subalpine  form) ;  Keddie  and  Portola,  Plumas  County,  California,  September,  1919,  Johns- 
ton (UC,  green  and  gray  forms  growing  together,  see  minor  variation  20);  branch  of 
Coconino  Wash,  Arizona,  Hall  11196  (UC);  Grand  Canon,  Arizona,  Eastwood  3636  (SF). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  BiGELOviA  BOLANDEiU  Gray,  Proc.  Am.  Acad.  8:641,  1873.— C.  parryi  bolanderi. 

2.  B.  HOWARDi  Parry,  in  Gray,  1.  c. — C.  parryi  howardi. 

3.  B.  HOWARDI  var.  attenuata  Jones.  Proc.  Calif.  Acad.  II,  5:691,  1895. — C.  parryi  attenuatus. 

4.  B.  HOWARDI  nevadensis  Gray,  1.  c. — C.  parryi  nevadensis. 

5.  B.  NEV.\.DENSis  Gray,  Syn.  Fl.  l':136,  1884. — C.  parryi  nevadensis. 

6.  B.  PARRYI  Gray,  Proc.  Am.  Acad.  8:642,  1873. — C.  parryi  typicus. 

7.  Chrysothamnus  affinis  Nelson,  Bot.  Gaz.  28:374,  1899. — A  variation  close  to  C.  parryi  attenuatus, 
which  was  made  a  variety  of  this  by  Nelson  (see  next  entry).  The  attenuation  of  the  bracts  is  intermediate 
between  this  and  subsp.  howardi,  while  the  low  number  of  bracts  (12  to  15)  and  the  yellowish-green  foliage  sug- 
gest subspecies  typicus.  The  upper  leaves  are  reduced  as  in  attenuatus  and  the  flowers  are  5  to  6  in  each  head. 
These  figures  are  derived  from  the  type  specimen  which  is  from  Jefferson,  South  Park,  Colorado  (August  29, 
1896,  Cowen,  Rocky  Mt.  Herb.). 

8.  C.  AFFINIS  ATTENUATUS  Nelson,  1.  c. — C.  parryi  attenuatus. 

9.  C.  ASPER  Greene,  Leaflets  1:80,  1904. — C.  parryi  asper. 

10.  C.  ATTENUATUS  Rydberg,  Bull.  Torr.  Club  37 :  130,  1910.— C.  parryi  attenuatus. 

11.  C.  BOLANDERI  Greene,  Erythea  3:114,  1895. — C.  parryi  bolanderi. 

12.  C.  HOWARDI  Greene,  1.  c,  113,  1895. — C.  parryi  howardi. 

13.  C.  MONOCEPHALUs  Nelson  and  Kennedy,  Proc.  Biol.  Soc.  Wash.  19:39, 1906. — C.  parryi  monocephalus. 

14.  C.  NEVADENSIS  Greene,  1.  c,  114,  1895. — C.  parryi  nevadensis. 

14a.  C.   NEVADENSIS  forma  monocephalus  Smiley,  Univ.  Calif.   Publ.   Bot.  9:357,    1921. — C.   parryi 

monocephalus. 
146.  C.  nevadensis  var.  vulcanicus  Smiley,  1.  c. — C.  parryi  vulcanicus. 

15.  C.  newberryi  Rydberg,  Bull.  Torr.  Club  31:652,  1904. — A  variation  of  C.  parryi  attenuatus  in  which 
the  tomentum  of  the  twigs  is  white  instead  of  yello%vish-green.  When  portions  of  the  types  of  these  two  are 
directly  compared,  no  other  difference  is  found.  Similar  color  variations  are  known  in  subspecies  howardi, 
and  in  C.  nauseosus  two  subspecies  {gnaphalodes  and  hololeucus)  are  distinguished  by  this  character,  but  here 
the  difference  extends  to  the  foliage  also,  other  features  furnish  supporting  characters,  and  the  two  commonly 
grow  side  by  side  but  with  no  evidence  of  intergradation.  The  type  of  newberryi  is  from  Canon  Largo,  New 
Mexico.  An  additional  citation  by  Rydberg  is  Mesa  Verde,  southwestern  Colorado,  September,  1892,  East- 
wood. At  the  University  of  California  this  latter  collection  includes  both  the  newberryi  form  and  a  twig,  prob- 
ably from  another  plant,  of  typical  attenuatus  with  the  usual  greenish  tomentum. 

16.  C.  PARRYI  Greene,  Erythea  3: 113,  1895. — C.  parryi  typicus. 

17.  C.  PAKRYI  ASPER,  but  with  shorter  and  wider  leaves,  the  average  about  2  cm.  long  by  2  mm.  wide,  and 
the  stipitate  glands  so  prominent  as  to  make  the  foliage  harsh  to  the  touch.  Lee  Canon,  Charleston  Mountains, 
Nevada,  at  8,000  feet  elevation.  Heller  11036  (UC).  This  specimen  is  only  1.5  dm.  high,  twice  as  broad,  and 
with  inflorescences  reduced  to  1  to  4  heads  each.  Somewhat  intermediate  to  true  asper,  especially  in  the  longer 
leaves,  is  a  collection  from  Alamo  Mountain,  Ventura  County,  California,  at  2,135  km.  {Hall  6701  UC). 

18.  C.  PARRYI  howardi,  but  much  reduced  in  stature  and  inflorescence  and  the  tomentum  of  the  steins 
white.  This  variation  is  confined  to  the  northern  part  of  the  range  of  howardi  and  has  the  appearance  of  a 
plant  contending  with  a  mora  rigorous  habitat  and  reduced  water-content.  It  is  represented  by  collections 
from  Carbon  County, Wyoming  (Goodding  537,  2016),  and  from  Albany  County,  Wyoming  {Goodding  2072, 
Nelson  8824). 

19.  C.  parryi  nevadensis,  but  with  linear-spatulate,  usually  greenish  leaves  only  1.5  cm.  long,  the  inflor- 
escence reduced  to  2-  or  3-headed  clusters  at  the  end  of  each  twig,  and  the  corollas  pink.  The  best  example 
is  a  plant  from  Spanish  Springs  Valley,  1,480  km.  elevation,  Washoe  County,  Nevada,  Kennedy  1050  (UC). 
The  same  form,  but  with  the  leaves  gray  tomentose  as  in  the  next,  comes  also  from  hills  around  Reno,  Nevada, 
September  20,  1910,  Heller  (DS,  UC).  These  and  otlier  Nevadan  collections  suggest  that  it  is  a  starved  form, 
perhaps  of  alkaline  or  otherwise  unfavorable  habitats. 


C.    PARRYI.  203 

20.  C.  PARRYI  NEVADENsis,  but  the  whole  herbage  white,  or  at  least  gray,  with  a  loose  tomentum.  West 
end  of  Pcavine  Mountain,  Nevada,  1,600  m.  elevation.  Heller  10675  (UC).  The  same  form  grows  also  at  Por- 
tola,  Plumas  County,  California,  Johnston  2180  (UC).  .\ccording  to  Johnston,  the  green  and  the  white  forms 
grow  intermingled  both  at  Portola  and  at  Keddie.  Although  no  intermediates  appear  as  to  color,  no  other 
distinguishing  characters  could  be  found.  This  appears  to  be  a  case  of  difference  in  a  single  character  and  per- 
haps the  result  of  mutation.  The  color  is  probably  influenced  by  the  amount  of  resinous  matter  secreted  by 
the  stems  and  leaves. 

21.  C.  vuLCANicus  Greene,  Leaflets  1:80,  1904. — C.  parryi  vulcanicus. 

22.  C.  WYOMiNGENSis  Nelson,  Bot.  Gaz.  28:372,  1899. — Not  finally  placed.  The  type  specimens,  from 
Buffalo,  Wyoming  {Nelson  2^95),  appear  to  be  a  variation  from  C.  parryi  typicm,  the  stems  being  leafy  to  the 
top,  the  inflorescence  elongated,  and  the  bracts  decidedly  acuminate.  But  the  leaves  are  narrow,  the  inflores- 
cence reduced  in  size,  and  the  flowers  only  5  in  the  small  head.  The  plants  grew  in  strongly  alkaline  soil,  which 
may  account  for  these  modifications,  or  it  is  possible  that  detailed  field  studies  will  demonstrate  wyomingensis 
as  a  modification  of  some  subspecies  of  C.  nauseosus.  Later  collections  from  BufTalo  {Nelson  8672),  identified 
as  this,  seem  to  be  a  form  of  C.  nauseosus  typicus,  at  least  in  part,  the  inflorescence  being  cymose  and  the  bracts 
only  acute. 

23.  LiNOSYRis  BOLANDERi  Gray,  Proc.  Am.  Acad.  7:354,  1868. — C.  parryi  bolanderi. 

24.  L.  HowARDi  Parry,  in  Gray,  1.  c,  6:541,  1865.— C.  parryi  howardi. 

25.  L.  HOWARDI  var.  nevadensis  Gray,  1.  c. — C.  parryi  nevadensis. 

26.  L.  PARRYI  Gray,  Proc.  Acad.  Phila.  1863:66,  1863.— C.  parryi  typicus. 

27.  Macronema  BOLANDERI  Greene,  Leaflets  1:81,  1904. — C.  parryi  bolanderi,  as  to  synonymy.  The 
probable  reason  for  this  transfer  has  been  already  discussed  (p.  160). 

RELATIONSHIPS. 

The  nearest  relatives  of  Chrysothamnus  parryi  are  undoubtedly  to  be  sought  among 
certain  forms  of  C.  nauseosus,  with  which  it  has  in  common  the  notably  pannose  tomen- 
tum of  the  twigs  and  similarly  shaped  corollas  and  style-branches.  While  the  inflores- 
cence is  of  the  racemose  rather  than  cymose  type,  individual  heads  are  sometimes  scarcely 
distinguishable  from  those  of  nauseosus,  except  by  the  loosely  arranged  bracts.  These 
are  always  more  attenuate  in  parryi  and  less  distinctly  ranked.  While  such  characters 
of  the  inflorescence  and  involucres  serve  well  for  specific  distinctions,  there  can  be  no 
doubt  as  to  the  common  origin  of  the  two  stocks. 

Among  the  assemblage  of  forms  here  considered  as  constituting  C.  parryi,  there  is  one 
with  an  appearance  so  strikingly  diff'erent  from  the  others  that  it  has  not  been  heretofore 
considered  as  conspecific  with  them.  This  is  the  original  C.  parryi,  here  made  the  basis 
of  subspecies  typicus.  It  belongs  to  a  portion  of  the  Rocky  Mountains  where  the  only 
other  subspecies  are  howardi  and  its  derivative  attenuatus,  both  very  diff'erent  in  appear- 
ance. If  it  were  not  for  the  occurrence  of  intermediate  forms  in  the  mountains  farther 
west,  parryi  and  howardi  might  both  be  maintained  as  major  species.  Their  marked 
difference,  however,  is  based  upon  only  vegetative  characters,  since  all  others,  such  as  the 
number  and  character  of  involucral  bracts  and  flowers,  exhibit  complete  series  of  inter- 
gradations,  as  indicated  in  table  22,  page  207.  As  compared  with  howardi,  typical  parryi 
is  a  more  robust  plant,  with  wider  and  longer  almost  strap-shaped  leaves  and  usually 
larger  heads.  No  intermediates  in  the  leaf  characters  are  found  and  the  two  are  appar- 
ently distinct  where  their  ranges  overlap.  Farther  west,  however,  we  find  such  sub- 
species as  vulcanicus,  with  leaves  as  long  as  in  typicus  but  narrow  as  in  howardi;  also 
asper,  with  leaves  as  broad  as  in  typicus  but  even  shorter  than  in  howardi;  while  in  neva- 
densis both  length  and  width  of  leaf  are  sufficiently  variable  to  satisfy  a  description  of 
either.  Since  none  of  these  can  be  separated  on  other  non-variable  characters,  they  seem 
to  indicate  that  the  whole  gamut  of  forms  is  of  a  common  and  modern  stock,  which  is  best 
accepted  as  a  single  major  species. 

As  in  the  case  of  typical  parryi,  every  attempt  has  been  made  to  find  stable  characters 
for  the  specific  separation  of  each  of  the  described  subspecies,  but  without  success.  None 
of  the  characters  heretofore  used  for  the  separation  of  species  is  of  more  importance  than 
those  used  in  the  key  to  the  subspecies.     Gray  (Syn.  Fl.  2'  136,  1884)  describes  the  leaves 


204 


GENUS   CHRYSOTHAMNUS. 


(     ^-'-'^^"'--^     )  \9monocep^2^ 


Inflonescence  In-Clorescence 

not  reduced  much  reduced 

Subalpine 


Fia.  27. — Phylogenetic  chart  of  the  subspecies  of  Chrysoihamnub  varryi 


C.    PARRYI.  205 

of  parryi  as  glabrous,  of  bolanderi  as  viscidulous.  In  all  specimens  of  parryi  examined 
the  leaves  are  minutely  glandular  and  often  also  puberulent.  The  "glandular-scabrous" 
character  assigned  by  Greene  to  asper  is  exactly  the  same  as  in  bolanderi,  except  that  the 
glands  are  slightly  stalked  and  thus  more  prominent.  Finally,  the  reduced  number  of 
heads  in  monocephalus  is  a  reaction  to  the  subalpine  environment  as  indicated  by  inter- 
mediate forms  at  lower  elevations  {Heller  9976).  A  similar  reduction,  although  not  car- 
ried to  such  an  extreme,  is  common  in  subspecies  asper  and  occasionally  in  howardi. 

In  attempting  to  trace  the  lines  of  evolution  within  the  species  it  is  necessary  to  keep 
in  mind  the  facts  of  geographic  distribution  as  well  as  the  morphology  of  the  various  sub- 
species and  minor  variations.  Thus,  the  close  phylogenetic  connection  between  typicus, 
of  the  Rocky  Mountains,  and  several  of  the  Sierra  Nevadan  subspecies  indicates  that  the 
distributional  areas  of  these  were  in  contact  during  some  past  period.  This  may  have 
occurred  in  or  near  the  area  now  known  as  the  Great  Basin,  where  the  earlier  climate  was 
much  less  arid  than  that  of  the  present  time  and  therefore  better  suited  to  the  growth  of 
these  mesophytic  types.  It  seems  that  over  this  central  area  there  may  have  grown  a 
primitive  form,  one  with  large  heads  of  numerous  flowers  and  bracts,  with  a  well-developed 
foliage,  and  with  no  special  structures  such  as  now  mark  some  of  the  more  highly 
specialized  subspecies.  Then,  as  greater  aridity  set  in,  this  primitive  stock  broke  up, 
forming  two  branches.  One  of  these  migrated  easterly  into  the  Rocky  Mountains,  and 
became  the  present  subspecies  typicus,  which  comes  so  close  to  fulfilling  the  requirements 
of  the  original  stock  just  assumed  that  it  is  placed  at  the  very  bottom  in  the  chart  of 
relationships.  The  other  branch  moved  to  the  westward,  finally  coming  to  rest  in  the 
Sierra  Nevada.  In  the  meantime,  this  western  migrant  underwent  modifications,  involv- 
ing especially  a  reduction  in  the  number  of  flowers  in  each  head  and  also  a  reduction  in 
the  inflorescence  itself.  These  changes  resulted  in  subspecies  bolanderi,  a  wide-leaved 
shrub  now  appearing  only  as  a  relict  in  the  middle  Sierra.  It  may  be  assumed  that  as 
bolanderi  migrated  into  the  western  plateaus  and  mountains  its  distribution  became  dis- 
continuous and  that  distinct  forms  were  evolved  in  the  different  areas.  At  any  rate,  there 
now  occurs  in  the  Siskiyou  Mountains  of  northern  California  a  subspecies  latior  which  has 
all  the  indications  of  being  a  lineal  descendant  of  bolanderi,  especially  in  the  still  further 
reduction  of  the  number  of  flowers.  The  somewhat  better  development  of  the  foliage 
and  the  more  elongated  inflorescence  may  be  either  persistent  traits  of  a  common  ancestor 
or  a  more  recent  adaptation  to  the  more  humid  habitat.  A  much  more  striking  modifica- 
tion is  subspecies  imulus,  now  stranded  in  the  high  mountains  of  southern  California. 
This  is  a  dwarf  with  very  short,  spatulate  leaves,  commonly  colored  involucres,  and  with 
the  whole  herbage  woolly.  The  appearance  is  so  unique  that  one  is  tempted  to  give  the 
form  specific  standing,  but  it  shows  no  variation  from  bolanderi  in  the  number  or  size  of 
flowers  and  bracts  or  in  any  other  feature  commonly  accepted  as  of  specific  value. 

The  six  remaining  subspecies  probably  are  all  more  recent  in  their  origin  than  those 
already  discussed.  This  is  evidenced  by  their  narrowed  leaves,  which  feature  enables 
them  to  cope  with  their  more  arid  environment,  and  especially  by  the  reduction  in  the 
number  of  flowers  in  each  head.  It  would  be  desirable  to  set  off  this  group  as  a  distinct 
species  (thus  preserving  the  established  name  of  howardi  in  specific  rank)  were  it  not  for 
latior,  which,  although  plainly  a  derivative  of  bolanderi,  has  the  flower  reduction  of  these. 
There  is  also  some  doubt  as  to  the  naturalness  of  the  assemblage,  as  will  be  noted  further 
on.  The  difficulties  in  the  way  of  such  a  treatment  are  seen  also  in  the  key  to  the  sub- 
species, where  no  clear-cut  division  can  be  made  between  these  and  the  earlier  subspecies. 
The  migratory  routes  taken  by  typicus  and  bolanderi  and  their  derivatives  doubtless 
were  followed  by  these  later  subspecies,  but  most  of  them  did  not  get  so  far  from  the 
original  center  of  distribution  and  at  least  two  {nevadensis  and  asper)  still  occupy  moun- 
tainous districts  well  within  the  Great  Basin  area. 


206  GENUS    CHRYSOTHAMNUS. 

The  members  of  this  second  major  division  of  Chrysothamnus  parryi  may  be  assembled 
into  two  apparently  natural  groups  of  three  subspecies  each.  One  of  these  groups  con- 
stitutes what  may  be  called  the  asper  line,  the  other  the  howardi  line,  the  two  differing 
chiefly  in  the  nature  of  the  involucre,  as  indicated  on  the  diagram  (fig.  27).  In  the  for- 
mer subgroup,  asper  is  given  a  central  position,  because  it  has  undergone  the  least  amount 
of  reduction  in  the  number  of  flowers  in  the  head.  Its  intermediate  geographic  position 
is  also  to  be  taken  into  account.  Farther  to  the  west  it  divides  into  two  branches.  One 
of  these  is  vulcanicus,  a  subspecies  of  the  higher  Sierra  Nevada,  which  differs  in  the  smaller 
average  number  of  flowers  and  also  in  the  loss  of  certain  xerophytic  features,  notably  the 
stalked  re.sin-glands.  There  is  evidence,  however,  that  the  two  thoroughly  intergrade 
along  the  east  slope  of  the  Sierra  Nevada  (see,  for  example,  Congdon's  numerous  collec- 
tions). The  other  branch  has  ascended  even  higher  and  culminated  in  subspecies  jnono- 
cephalus,  which  has  all  of  the  characteristics  of  a  subalpine  derivative,  the  stems  being 
low  and  divergently  branched,  the  inflorescence  reduced  to  one  or  two  heads  among  the 
upper  leaves,  and  the  foliage  gray  with  a  fine  though  sparse  tomentum.  It  is  not  impos- 
sible that  monocephalus  is  a  subalpine  derivative  of  subspecies  nevadensis,  and  possibly  it 
is  polygenetic  in  origin. 

The  howardi  line  consists  of  three  primary  and  several  secondary  derivatives.  The 
subspecies  howardi  itself  is  a  common  form  in  the  Rocky  Mountains  and  differs  from  the 
others  of  its  line  by  the  presence  of  elongated  upper  leaves  and  involucral  bracts  that  are 
only  moderately  attenuate.  An  unnamed  modification,  differing  chiefly  in  the  short 
congested  inflorescence,  occurs  in  Wyoming.  It  is  discussed  under  minor  variation  18. 
The  connection  between  nevadensis  and  howardi  is  not  direct,  and  possibly  it  passes 
through  atlenuatus;  nevadensis  belongs  to  the  desert  mountains  and  is  itself  polymorphous. 
The  derivation  of  attenuatus  from  howardi  is  more  easily  demonstrated,  since  intermediate 
stages  are  represented  by  existing  forms.  Such,  for  example,  is  a  form  from  Panguitch 
Lake,  Utah  {Jones  5994,  6002z)  in  which  the  bracts  are  almost  as  slender  as  in  attenuatus, 
and  another  from  South  Park,  Colorado,  which  is  almost  the  same  but  with  a  reduced 
number  of  bracts  (minor  variation  7).  Finally,  there  is  to  be  noted  a  possible  connection 
through  attenuatus  and  its  variation  newherryi  (minor  variation  15)  to  C.  nauseosus  hige- 
lovi  and  thence  to  other  members  of  C.  nauseosus. 

The  accompanying  diagram  (fig.  27)  is  intended  to  express  graphically  the  ideas  of 
relationships  as  above  set  forth.  It  is  quite  possible  that  the  lines  of  evolution  have  been 
different  from  those  here  indicated;  for  example,  vulcanicus  and  its  derivatives  may  have 
arisen  from  a  bolanderi-like  ancestor  after  this  was  evolved  from  typicus.  Even  if  this 
could  be  demonstrated,  it  would  not  greatly  modify  the  position  of  the  subspecies  as  given 
in  the  diagram  and  it  is  believed  that  those  there  brought  near  to  one  another  are  of  close 
genetic  relationship,  even  though  the  direction  of  the  evolutionary  current  may  be  in 
doubt. 

ECOLOGY  AND  USES. 

Chrysothamnus  parryi  forms  characteristic  societies  in  climax  grassland,  its  low  stature, 
and  dense  growth  suggesting  certain  subspecies  of  C.  viscidifiorus,  as  well  as  Gutierrezia. 
Both  typicus  and  howardi  are  frequent  in  the  mixed  prairie,  the  latter  being  found  over 
wide  stretches  in  the  foothills,  on  elevated  plains,  and  in  the  lower  mountain  parks, 
while  the  former  occurs  in  the  moister  parks  at  higher  altitudes.  Howardi  is  also 
frequently  found  on  rocky  slopes  and  ridges,  as  an  open  subclimax  community.  This 
is  in  harmony  with  the  fact  that  both  forms  are  indicators  of  a  somewhat  greater 
water-content.  They  occur  in  the  original  mixture  of  Bouteloua,  Siipa,  and  Agropyrum, 
but  are  most  abundant  in  grama  short-grass,  owing  to  their  increase  under  grazing. 
They  are  frequently  associated  with  Artemisia  frigida,  Antennaria  dioeca,  Chrysothamnus 


C.    PAKRYI. 

Table  22. — Variation  in  the  subspecies  of  Chrysothamnus  parryi.' 


207 


No.  of 
flowers 
per  head. 


Length, 

including 

lobes. 


Lobe- 
length. 


Ratio  of 
lobe- 
length 
to  total 
length. 


Subspecies  typicus: 

Big  Creek,  Wyo 

Golden  Gulch,  Wyo 

Albany  County,  Wyo. . 
Larimer  County,  Colo. . 

Montrose,  Colo 

Tolland,  Colo 

Breekenridge,  Colo. .  .  . 


Do. 


Cumbres,  Colo 

Leadville,  Colo 

Minturn,  Colo 

Near  Del  Norte,  Colo 

San  Juan  Mountains,  Colo. 

Near  Empire,  Colo 

West  Central  Colo 

Southwestern  Colo 

Cerro  Summit,  Colo 

Hayden,  Colo 

Sevier  River,  Utah 


10663  R 
7580  R 

69421  UC 
69423  UC 
81867  R 
76070  R 
30580  R 
13221  R 
22893  R 
11056  CI 
11054  CI 
11101  CI 

205815  UC 
31169  UC 
55160  UC 

172775  UC 
55166  UC 

69422  UC 
159880  UC 


Average . 


Subspecies  bolanderi: 

Mono  Pass,  Calif,  (type) . 
Duplicate  type 


Average . 


i  latior: 

Mount  Eddy,  Calif,  (type) 

Duplicate  type 

Eastwood  2079 

Mount  Shasta,  Calif.  Grant  6152 

Canby  111 

Modoc  County,  Calif 


SF 

Gr 

205549  UC 

62938  UC 
Gr 

75822  UC 


Average 

Subspecies  imulus: 

San     Bernardino     Mountains, 

Calif,  (type) 

Do 


Average. 


Subspecies  asper: 

Inyo  County  Calif,  (type) . . . 

Bloody  Canon,  Calif 

Charleston  Mountains,  Nev.' 
Ventura  County,  Calif 


206S49  US 
31165  UC 

171476  UC 
68942  UC 


Average . 


Subspecies  vulcanicus: 

Mono  MUls,  Calif 

Volcano  Creek,  Calif,  (type  coll.) 
Eastern  Tulare  County,  Calif. 

Little  Kern  River,  Calif 

Tulare  County,  Calif 


203167  UC 
Gr 
126456  UC 
126547  UC 
134760  UC 


Average . 


10.0 
10.0 
9.0 


12.0 
10.0 
10.0 
10.1 
11.0 
11.0 
9.0 
9.1 
11.0 
11.0 
9.0 


14 

11 

12  13 


p.ct. 
25 
23 
21 


10.0 
10.0 
9.0 


13.0 

12.0  14.0 

13.0 


11.0 

.0  12.0 

12.0 


11.0 
Young. .  . . 


12.0 
10.5 
11.0 


11   13 

12 

9  12 


6  6 
6  8  10 
5     5     4 

9  10 


11.5 
12.0 
11.0 
13.0 


10 


9.0 
11.0 
10.2 


10.1 


15 


'  Except  where  otherwise  mentioned  the  plants  selected  for  measurement  are  normal  and  fairly  representative  of  the 
subspecies  to  which  they  are  assigned.  The  figure  given  is  the  average  of  a  number  of  measurements,  but  the  fluctuation 
usually  is  slight  on  any  given  plant.  In  the  case  of  involucres  and  corollas  only  the  larger  ones  were  measured,  on  the  as- 
sumption that  the  smaller  ones  were  not  fully  developed.  '  Minor  variation  17. 


208 


GENUS   CHKYSOTHAMNUS. 
Table  22. — Variation  in  the  subspecies  of  Chrysothamnus  parryi — Continued. 


Herbarium. 

Involucre. 

No.  of 
flowers 
per  head. 

Corolla. 

Length. 

No.  of 
bracts. 

Length, 

including 

lobes. 

Lobe- 
length. 

Ratio  of 
lobe- 
length 
to  total 
length. 

Subspecies  monocephalus: 

MountRose.Nev., 3,320m.  alt.  . 
Mount  Rose,  Nev.,  3,170  m.  alt.  . 

76001  UC 
176764  UC 

31166  UC 
195489  UC 

mm. 
11.0 
10.5 
10.0 
10.1 

12 
10 
10 

8 

5 

5     6 

5 

5 

7.6 
9.3 

8.0 
7.7 

1.0 
1.5 
1.0 
1.3 

p.ct. 
13 
16 
12 
17 

Mono  County  Calif 

10.4 

10 

5 

8.1 

1.2 

14 

Subspecies  howardi: 

Bells  Springs,  Carbon  County, 
Wyo'   . 

51498  UC 

69420  UC 

CI 

CI 

23595  R 

69419  UC 

47263  R 

CI 

CI 

CI 

203169  UC 

11089  CI 

203168  UC 

205813  UC 

205814  UC 

10 

12 

10.8 

12.0 

11.1 

13 

13.0 

9.5 
11.0 

9.8 
12 

11.0 
10 
10.0 

9.9 

14 

13 
11   14 
15 
11 
13 
14 
14 
13 
11 
19 
15 
14 
12 
12 

5 

5 
4 
5 
5 
6 
6 
5 
6 
5 
5 
5 
7     6 
6 
5 

8.1 

8.0 
8.0 
8.0 
9.5 
10.6 
10.7 
9.0 
8.5 
8.0 
10.0 
10.1 
10.0 
9.5 

1.3 

1.3 
1.4 
2.0 
2.1 
1.7 
2.5 
1.2 
1.2 

1.5 
1.4 
1.0 
1.7 
1.5 

16 

16 
18 
25 
22 
16 
23 
13 
14 
14 
15 
14 
10 
18 
16 

Encampment,  Carbon  County, 

West  of  Palmer  Lake,  Colo 

Walsenberg,  Eastern  Colo 

West  of  Walsenberg,  Colo 

CafSon  City,  Colo 

San  Luis  Valley   Colo 

U.O 

13.6 

6.1 

9.1 

1.5 

17 

Subspecies  allenualus: 

CI 

187573  UC 

159552  UC 
■159554  UC 

159553  UC 
159789  UC 
179590  UC 

11.0 
10.5 
10.0 
11.5 
11.0 
10.2 
10.5  12 

5 
5 
5 
5 
6 
5 
6 

9.0 
10.1 
10.0 
10.0 
10.2 
10.0 
10.6 

0.6 
1.5 
0.7 
11 
1.5 
0.5 
1.7 

7 
15 

7 
11 
15 

5 
16 

Rio  Mancos,  Colo. 

13 
13 
14 
13  15 
13 
13 

Thurber,  Utah 

Marysvale,  Utah  (type  coU.).  .  . 
Marysvale,  Utah 

Near  Panguitch  Lake,  Utah. .  . . 
Star  Peak,  Nev.  (off  type) 

10.7 

13 

5 

9.9 

1.0 

11 

Subspecies  nevadensis: 

West  Humboldt  Mountains,  Nev. 

US 
179575  UC 

75412  UC 
176431  UC 
176855  UC 

87228  UC 
193101  UC 
134301  UC 
203269  UC 
203263  UC 
203265  UC 

13.3 
12.0 
11.5 
14.0 
11.0 
15.0 
13.0 
15.0 
14.0 
12.0 
13.0 

13 

13 
15 
18 
14 
15 
13 
13 
14 
14 

6 
5 
5 
5 
4 
5 
6 
6 
6 
5 
5 

10.5 
9.5 
9.9 
10.1 
7.1 
10.1 
10.5 
10.1 
10.1 
9.8 
9.1 

1.5 
1.3 

1.3 
1.0 
1.2 
1.5 
1.0 
1.5 

1^2 

14 
14 

13 
14 
12 
14 
10 
15 

13 

Washoe  County,  Western  Nev. 
Do2 

Ormsby  County,  Western  Nev. . 
Verdi   Western  Nev 

Portola,  Calif.' 

Do 

13.0 

14 

5 

9.7 

1.2 

13 

Minor  variation  18. 


'  Minor  variation  19. 


'  Minor  variation  20. 


V.  pumilus,  Lupinus  argenteus,  etc.,  while  howardi  is  often  in  contact  with  C.  n.  pinifolius. 
Nevadensis  likewise  forms  societies  in  the  bunch-grass  prairie  and  in  the  sagebrush 
association  of  western  Nevada  and  adjacent  California,  but  it  also  extends  to  timber- 
line  in  open  parks  and  savannahs.     The  remaining  subspecies  are  all  of  less  importance. 


C.    NAUSEOSUS.  209 

They  are  practically  confined  to  the  mountains  of  California  from  the  chaparral  belt 
upward,  monocephalus  in  particular  reaching  timber-line. 

While  Chrysothamnus  parryi  is  browsed  more  or  less  during  drought  periods,  especially 
the  abundant  typicus  and  howardi,  it  is  to  be  regarded  as  a  range  weed,  valuable  only  as 
an  indicator  of  the  degree  to  which  over-grazing  has  proceeded. 

12.  CHRYSOTHAMNUS  NAUSEOSUS  (Pallas)  Britton,  in  Britten  and  Brown,  III.  Fl.  3:326, 
1898.    Plates  33  to  35. 

Shrub  usually  3  to  20  dm.  high,  but  varying  from  mere  dwarfs  to  arborescent  forms  25 
dm.  high,  commonly  with  several  erect  stems  from  the  base,  these  branching  to  form 
rounded  bushes;  bark  of  main  stems  brown,  fibrous;  twigs  flexible,  erect,  moderately 
leafy,  covered  with  a  closely  packed  gray-green  or  white  felt-like  tomentum,  which  is 
deciduous  only  after  several  years,  striate  when  the  tomentum  is  smooth-surfaced  but  the 
striae  masked  when  the  surface  is  loose  and  fluffy;  leaves  varying  from  nearly  filiform  to 
broadly  linear,  not  twisted,  acute,  2  to  7  cm.  long,  0.5  to  5  mm.  wide,  1-  to  3-nerved,  not 
rigid,  more  or  less  tomentulose  but  sometimes  practically  glabrous;  heads  in  terminal 
rounded  cymes,  these  sometimes  compound  and  forming  elongated  round-topped  thyrses; 
involucre  6  to  13  mm.  high;  bracts  usually  20  to  25,  in  vertical  ranks,  lanceolate,  acute  or 
obtuse,  firm,  glabrous  to  densely  tomentose,  without  herbaceous  tips;  flowers  usually  5, 
rarely  6;  corolla  tubular-funnelform,  passing  imperceptibly  from  tube  to  throat,  7  to  10 
or  rarely  12  mm.  long,  either  glabrous  or  puberulent  or  arachnoid-pubescent  on  the  tube; 
lobes  0.4  to  2.5  mm.  long,  erect  to  spreading,  glabrous  or  sparsely  pubescent;  anther-tips 
lanceolate,  acute,  0.4  to  0.7  mm.  long;  style-branches  long-exserted,  the  linear-filiform 
acute  appendage  nearly  equaling  or  usually  much  exceeding  the  stigmatic  portion; 
achenes  narrowed  below,  5-angled,  5  to  5.5  mm.  long,  densely  strigose  or  subvillous  to 
glabrous;  pappus  shorter  than  or  slightly  exceeding  the  corolla,  comparatively  rigid, 
dull  white.     (Chrysocoma  nauseosa  Pallas  in  Pursh,  Fl.  Am.  Sept.  2:517,  1814.) 

On  the  plains  and  in  the  mountains,  chiefly  of  the  Great  Basin  area,  but  extending 
from  Saskatchewan  and  the  Dakotas  to  Colorado,  western  Texas,  northern  Sonora,  Lower 
California,  the  inner  Coast  Ranges  of  upper  California,  eastern  Washington,  eastern 
British  Columbia,  and  Alberta. 

SUBSPECIES. 

The  specific  limits  here  set  for  C.  nauseosus  are  somewhat  more  extended  than  those 
assigned  in  any  previous  treatment,  excepting  only  a  recent  one  by  Hall  (Univ.  Calif. 
Publ.  Bot.  7:159  to  181,  1919).  The  species  comprises  a  multitude  of  forms,  from 
among  which  47  segregates  have  been  technically  described.  All  but  eight  of  these  have 
been  accorded  specific  rank  at  one  time  or  another.  The  difficulties  encountered  in  an 
attempt  to  assign  specific  or  even  varietal  rank  to  all  of  the  forms  is  indicated  by  the 
following  quotation  from  page  161  of  the  paper  just  referred  to: 

"Notliing  can  be  more  certain  than  that  these  forty-two  [now  forty-seven]  attempts  to  recognize  species 
and  varieties  do  not  by  any  means  exhaust  the  resources  of  the  group.  Every  autumnal  excursion  into  a  new 
district  brings  to  hglit  one  or  more  forms  not  previously  described.  The  only  limits  set  to  the  number  of  new 
species  or  varieties  which  might  be  set  up  lie  in  one's  ability  to  visit  all  parts  of  the  field  during  the  flowering 
period  and  the  failure  or  disinclination  to  recognize  minute  variations.  But  the  systematist  should  include 
in  his  ultimate  object  not  only  the  recognition  of  this  multitude  of  forms,  but  also  their  proper  arrangement 
in  a  scheme  which  will  display  their  natural  relationships.  Since  this  would  entail  an  enormous  amount 
of  detailed  labor,  including  extensive  experiments,  and  since  the  results,  even  if  attainable,  would  be  of  but 
little  practical  value  at  the  present  time,  the  writer  has  satisfied  himself  with  the  acceptance  of  twenty-two 
forms,  all  of  which  are  treated  as  varieties.  This  is  believed  to  provide  for  all  of  the  principal  forms,  and 
it  is  quite  certain  that  each  of  the  described  varieties  is  a  natural  unit,  although  in  most  cases  it  is  itself  made 
up  of  still  smaller  variants." 


210  GENUS   CHRYSOTHAMNTJS. 

Artificial  Key  to  the  Subspecies  of  Chrysothamnus 

Involucres  puberulent  fat  least  the  short  outer  bracts)  or  tomentulose  to  densely  woolly; 
foliage  mostly  gray  or  even  white  with  a  rather  copious  pubescence 
(least  pronounced  in  speciosus  and  sometimes  yellowish-green  in 
turbinatus,  bigelovi,  and  glareosus). 
Achenes  densely  pubescent. 

Tomentum  loose,  copious,  and  nearly  pure  white  on  twigs  and  leaves,  extending  to 
the  involucres;  corolla-tube  often  arachnoid-pubescent. 
Inner  bracts  of  involucre  plainly  tomentose  or  if  nearly  glabrous  the  bracts  then 
acute. 
CoroUa-lobes  lanceolate,   1   to  2  mm.   long;  style-appendage  longer  than  the 

stigmatic  part (e)  albicaulis  (p.  212). 

Corolla-lobes  short-ovate,  less  than  1  mm.  long;  style-appendage  shorter  than 

the  stigmatic  part (6)  hololetteus  (p.  211). 

Inner  bracts  smooth  and  glabrous  or  nearly  so,  very  obtuse (d)  latisquameus  (p.  212). 

Tomentum  close,  compact,  smooth,  and  gray  or  white  on  twigs,  the  leaves  gray  or 
greenish  and  sometimes  nearly  glabrous;  corolla-tube  glabrous  or 
puberulent,  only  rarely  arachnoid-pubescent. 
Bracts  gradually  acute  or  somewhat  obtuse. 
Involucre  6  to  9  or  rarely  10  mm.  high.^ 

Shrubs  only  2  to  6  dm.  high;  corolla  6.5  to  8  mm.  long'  (very  rarely  9  mm.) .  .   (/)   typicus  (p.  213). 

Shrubs  normally  4  to  20  dm.  high;  corolla  8  to  10  mm.  long  or  rarely  only 

7  mm.  in  gnaphalodes-  (latisquameus  of  Arizona  and  New  Mexico, 

with  broad  and  very  obtuse  and  smooth  inner  bracts,  might  be 

sought  here). 

Corolla-lobes  1  to  2  mm.  long;  style-appendage  longer  than  stigmatic  portion. 

Leaves  1  to  3  mm.  wide,  1-nerved;  bracts  various  but  mostly  acute (c)   speciosus  (p.  211). 

Leaves  3  to  5  mm.  wide,  3-nerved;  bracts  mostly  obtuse (g)  salicifolius  (p.  213). 

Corolla-lobes  0.5  to  1  mm.  long;  style-appendage  shorter  than  stigmatic 

portion (o)  gnaphalodes  (p.  211). 

Involucre  11  to  12  mm.  or  rarely  only  10  mm.  high.'     (Involucres  of  turbinattis, 
if  shorter,  may  be  known  by  their  cybndric  shape.) 

Corolla-lobes  about  0.5  mm.  long,  villous (q)  turbiriatus  (p.  217). 

Corolla-lobes  nearly  2.0  mm.  long,  glabrous (i)   bernardinus  (p.  214). 

Bracts  abruptly  acute.     Far  western \h)  occidentalis  (p.  213). 

Achenes  glabrous. 

Bracts  of  the  involucre  obtuse;  corolla  10  to  12  mm.  long (r)  glareosus  (p.  217). 

Bracts  of  the  involucre  very  acute;  corolla  9  to  10  mm.  long (s)   bigelovi  (p.  217). 

Involucres  perfectly  glabrous,  although  sometimes  viscidulous  or  glandular;  foUage  mostly 
greenish,  the  tomentum  rather  sparse  or  wanting  on  mature  leaves. 

Achenes  glabrous  or  nearly  so : (t)   leiospermus  (p.  217). 

Achenes  densely  pubescent. 

Leaves  linear,  mostly  more  than  1  mm.  wide,'  mostly  1-  to  5-nerved. 

Involucre  10  mm.  or  more  long;  corolla  9  to  12  mm.  long;  lobes  1.5  to  2.5  mm.  long. 

Southern  California (i)    bernardinus  (p.  214). 

Involucre  6  to  8  mm.  long,  corolla  7  to  9  mm.  long;  lobes  0.5  to  1.5  mm.  long (J)   graveolens  (p.  214). 

Leaves  linear-filiform  or  very  narrowly  linear,  mostly  1  mm.  or  less  wide  (except  in 
occidentalis),  1-nerved. 
Bracts  of  the  involucre  obtuse  to  acute,  not  abruptly  pointed. 

Corolla-lobes  glabrous;  shrub  leafy  except  sometimes  in  mohavensis. 

Involucre  7  to  9  mm.  long,  not  sharply  angled,  the  bracts  moderately  keeled, 
5-rowed. 
Corolla  7  to  9  mm.  long;  lobes  under  2  mm.;  twigs  and  foliage  slender. 
Lobes  of  corolla  0.5  to  1  mm.  long,  rarely  more:  inflorescence  typically 

rounded  to  pyramidal.     Rocky  Mountain  States (A;)  pinifolius  (p.  215). 

Lobes  of  corolla  1  to  2  mm.  long,  inflorescence  typically  cylindric  to  pyram- 
idal.    Great  Basin (I)   consimilis  (p.  215). 

Corolla  7  to  10  mm.  long;   lobes  1.7  to  2.5  mm.  long;  twigs  and  foliage 

stouter.     Southwestern (m)  viridvlus  (p.  215). 

Involucre  9  to  10  mm.  long,  sharply  5-angled,  the  strongly  keeled  bracts  in 

very  distinct  vertical  rows (o)  mohavensis  (p.  216). 

Corolla-lobes  sparsely  long-hairy  in  the  bud;  shrub  nearly  leafless (p)  junceus  (p.  216). 

Bracts  of  the  involucre  abruptly  pointed  or  some  only  acute.     Far  western. 

Tip  of  the  bract  short,  erect (h)  occidentalis  (p.  213). 

Tip  of  the  bract  about  1  mm.  long,  very  slender,  recurved (n)  ceruminosus  (p.  216) . 

'  A  natural  key  has  not  been  prepared,  but  the  groupings  according  to  a  natural  system  are  given  in  figure  28,  page  223. 
'  These  measurements  are  of  fully  mature  involucres  and  corollas,  the  latter  either  fresh  or  restored  by  boiling. 
•  Care  must  be  exercised  in  making  this  measurement  since  the  leaves  are  often  longitudinally  folded.     The  figures  given 
are  for  the  total  width  of  the  fiat  leaf. 


C.    NAUSEOSUS.  211 

The  difficulties  encountered  in  an  attempt  to  assign  specific  rank  to  the  more  striking 
variations  are  indicated  somewhat  in  table  23,  where  the  principal  characters  are  tabu- 
lated. The  principal  characteristics  of  the  20  subspecies  are  given  in  the  key  on  page  210 
and  the  subspecies  themselves  are  given  a  diagrammatic  presentation  on  page  223. 

12a.  Chrysothamnus  naxjseosus  gnaphalodes  (Greene). — Shrub  5  to  15  or  rarely  25 
dm.  high,  usually  globoid  in  outline,  with  very  many  short  twiggy  branches;  twigs  erect 
or  spreading,  not  densely  leafy,  obscurely  striate,  yellowish  green  or  gray  with  a  closely 
packed  tomentum;  herbage  usually  very  fragrant;  leaves  2  to  4  cm.  long,  1  mm.  or  less 
wide,  those  of  the  end  twigs  only  1  to  3  cm.  long  and  often  recurved,  1-nerved,  gray- 
tomentose;  inflorescence  a  rounded  cyme  terminating  each  of  the  twigs;  involucre  about 
7  (6  to  8)  mm.  high;  bracts  rather  obtuse,  keeled,  in  5  distinct  vertical  rows,  tomentose, 
not  ciliate;  corolla  7  to  8  mm.  long;  tube  sparsely  pubescent  with  short  crisp  or  rigid 
hairs;  lobes  ovate,  acute,  0.5  to  1  mm.  long,  erect  or  even  connivent  around  the  stamen- 
tube;  style-appendage  shorter  than  the  stigmatic  part;  achenes  densely  pubescent. 
(C.  speciosus  var.  gnaphalodes,  Greene,  Erythea  3:110,  1895.)  Abundant  on  gravelly 
and  sandy  non-alkaline  slopes  and  benches  of  western  Nevada,  eastern  California  (and 
northern  Arizona?).  Tj^pe  locality,  Pyramid  Lake,  Nevada.  Collections:  Pyramid 
Lake,  Nevada,  1883,  Curran  (Univ.  Calif.  Herb.  87247,  probably  the  type);  Fallon, 
Nevada,  Heller  10680  (DS,  Gr,  NY);  California:  Benton,  Mono  County,  Hall  10655 
(UC);  White  Mountains,  Inyo  County,  Hall  10631  (UC);  west  of  Lancaster,  Los  Ange- 
les County,  Hall  10585  (SF,  UC);  Banning,  westerly  edge  of  Colorado  Desert,  September 
27,  1894,  Tourney  (UC);  mesas  near  Colton,  Parish  2057  (DS). 

126.  Chrysothamnus  natjseosus  hololeucus  (Gray).^ — Shrub  6  to  18  dm.  high  and 
fully  as  broad,  closely  branched  and  usually  of  rounded  outline;  twigs  erect,  leafy  to  the 
top,  not  striate,  white  with  a  permanent  dense  tomentum ;  herbage  exceedingly  fragrant ; 
leaves  linear,  1  to  3  cm.  long,  about  1  but  sometimes  nearly  2  mm.  wide,  1-nerved,  per- 
manently white-tomentose ;  inflorescence  a  rounded  often  compact  cyme;  involucre  6  to 
7  mm.  high;  bracts  very  obtuse,  plainly  keeled  and  in  5  distinct  vertical  ranks,  woolly 
but  not  ciliate;  corolla  6.5  to  8  mm.  long;  tube  minutely  puberulent  and  also  more  or  less 
cobwebby  with  loose  hairs  or  these  occasionally  wanting;  lobes  ovate,  acute,  strictly 
erect,  0.5  to  1  mm.  long;  style-appendage  shorter  than  the  stigmatic  part;  achenes  densely 
pubescent.  (Bigelotda  graveolens  var.  hololeuca  Gray,  Proc.  Am.  Acad.  8:645,  1873.) 
Gravelly  or  sandy  well-drained  slopes  of  western  Nevada  and  eastern  California  extending 
southward  as  far  as  Antelope  Valley.  Type  locality,  Owens  Valley,  California.  Col- 
lections: Sutcliffe,  Pyramid  Lake,  Nevada,  Hall  10884  (UC);  near  Lida,  Esmeralda 
County,  Nevada,  Hall  10818  (UC);  Benton,  Mono  County,  California,  Hall  10643  (UC); 
Independence,  Inyo  County,  California,  Hall  10615  (SF,  UC);  type  collection,  Horn  (Gr). 

12c.  Chrysothamnus  nauseosus  speciosus  (Nuttall). — Shrub  commonly  6  to  20  dm. 
high  (or  only  4  dm.  in  the  far  west),  broad  and  rounded;  twigs  mostly  erect,  with  long 
leaves  to  the  summit,  striate  but  the  striae  often  obscure,  greenish  white,  the  tomentum 
comparatively  smooth;  herbage  nearly  inodorous;  leaves  linear,  2  to  6  cm.  long,  typically 
about  1  mm.  wide  but  varying  to  3  mm.  (see  minor  variation  58);  1-nerved,  usually  erect 
or  ascending,  becoming  dense  toward  the  inflorescences  and  there  scarcely  reduced  in  size, 
gray,  tomentose  or  the  tomentum  partly  deciduous  and  the  foliage  then  greenish;  inflor- 
escence a  round-topped  or  somewhat  elongated  cyme,  commonly  loose;  involucre  8  to 
10  mm.  high ;  bracts  acute,  strongly  keeled,  in  obvious  vertical  rows,  either  tomentulose 
on  the  back  or  all  but  the  very  short  outermost  ones  glabrous  (as  in  the  tjqDe),  not  ciliate; 
corolla  8  to  10  or  rarely  11  mm.  long;  tube  sparsely  puberulent  or  glabrous;  lobes  0.8  to  2 
mm.  long;  style-appendage  longer  than  the  stigmatic  part;  achenes  densely  pubescent. 


212  '  GENUS   CHRYSOTHAMNUS. 

(C.  spedosus  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:323,  1840.)  Sandy  and  clayey  slopes 
and  benches,  where  only  moderately  alkaline,  Montana,  Wyoming,  and  western  Colorado 
to  Utah,  eastern  California,  Washington,  and  Idaho.  Type  locality,  in  the  Rocky 
Mountain  plains,  near  Lewis  River.  Collections:  Type  collection,  Nuttall  (Gr,  Phila); 
Fremont  County,  Wyoming,  Goodding  521  (NY,  UC) ;  Woods  Landing,  Wyoming,  Nelson 
3477  (R,  type  of  C.  pulcherrimus  Nelson,  minor  variation  68);  North  Elk  Canon,  Rio 
Blanco  County,  Colorado,  September  3,  1902,  Sturgis  (Gr,  leaves  3  mm.  wide,  tomentum 
dense  and  stopping  abruptly  with  the  outer  involucral  bracts  exactly  as  in  the  type); 
North  Park,  Colorado,  Osterhout  2266  (NY) ;  near  Hebron,  Colorado,  Shear  l^SJ^l  (NY) ; 
Parleys  Canon  near  Salt  Lake  City,  Utah,  Jones  511  (UC);  Ogden,  Utah,  September  28, 
1917,  Stilwell  (UC);  Fall  Creek,  Ormsby  County,  Nevada,  Baker  I4S6  (Gr,  UC,  SF, 
minor  variation  58);  Mono  Pass,  California,  Bolander  6145  (Gr,  NY,  US,  same  vari- 
ation); Leevining  Canon,  Mono  County,  California,  Hall  10852  (UC,  same  variation); 
near  Yreka,  Siskiyou  County,  California,  Butler  1824  (UC);  Crater  Lake,  Oregon, 
2,750  m.  altitude,  Heller  12945  (DS,  SF,  UC);  near  Echo,  eastern  Oregon,  Leiberg  906 
(DS,  Gr,  UC,  tall,  erect  form  with  strongly  pubescent  involucres,  minor  variation  57); 
Cow  Creek,  mouth  of  Doe  Creek,  Douglas  County,  Oregon,  Ward  43  (NY,  typical). 

12d.  Chrysothamnus  nauseosus  latisqtjameus  (Gray). — Shrub  tall  (perhaps 
rounded  at  top) ;  twigs  erect  or  ascending,  leafy  to  the  summit,  the  striae  obscured  by  a 
white  rather  loose  tomentum;  herbage  probably  mildly  fragrant;  leaves  2  to  5  cm.  long, 
less  than  1  mm.  wide ;  inflorescence  a  loosely  branched  rounded  compound  cyme;  involucre 
about  8  mm.  high  (7  to  9  mm.) ;  bracts  very  obtuse  (at  least  the  inner  ones),  carinate,  in  5 
distinct  vertical  rows,  outermost  ones  tomentulose,  inner  ones  usually  glabrous;  corolla 
about  8  to  9  mm.  long ;  tube  short-pubescent  or  glabrous ;  lobes  ovate  or  short-lanceolate,  0.5 
to  1  mm.  long,  erect;  style-appendage  longer  than  the  stigmatic  portion;  achenes  densely 
pubescent.  (Bigelovia  graveolens  var.  latisquamea  Gray,  Proc.  Am.  Acad.  8:645,  1873.) 
New  Mexico,  Arizona,  and  Sonora.  Type  locality.  New  Mexico.  Collections :  Type  col- 
lections, October  2,  1853  or  1854,  Bigelow,  and  on  the  Mimbres,  1853,  Henry  (Gr);  San 
Lorenzo,  Grant  County,  New  Mexico,  Metcalfe  1462  (DS,  Gr,  NY,  US);  Burro  Moun- 
tains, New  Mexico,  Rushy  202  (US);  Santa  Rita  Mountains,  Arizona,  November,  1891, 
Brandegee  (UC,  type  collection  of  C.  spedosus  arizonicus  Greene,  minor  variation  73); 
Billings,  Arizona,  Jones  4511  (NY,  US);  Santa  Cruz,  Sonora,  Mearns  2624  (US). 

12e.  Chrysothamnus  nauseosus  albicaulis  (Nuttall). — Shrub  5  to  10  dm.  high,  of 
rounded  outline;  twigs  erect,  leafy  to  the  top,  not  evidently  striate,  white  with  a  per- 
manent and  dense  tomentum;  herbage  not  fragrant;  leaves  narrowly  linear,  2.5  to  4  cm. 
long,  0.5  to  1.5  mm.  wide  or  up  to  3  mm.  wide  in  occasional  forms,  1-nerved,  permanently 
and  floccosely  white-tomentose;  inflorescence  a  rather  loose  round-topped  cyme;  invol- 
ucre 7  to  9  mm.  high;  bracts  mostly  acute,  plainly  keeled,  in  5  distinct  vertical  ranks, 
white-woolly  but  not  ciliate;  corolla  8  to  10  mm.  long;  tube  usually  arachnoid  with 
long  weak  hairs;  lobes  lanceolate,  1.5  to  2  mm.  long;  style-appendage  longer  than  the 
stigmatic  part;  achenes  densely  pubescent.  (C.  spedosus  I3.  albicaulis  Nuttall,  Proc. 
Am.  Phil.  Soc.  II,  7:324,  1840.)  Upland  slopes  and  benches,  most  plentiful  in  the  basin 
of  the  Columbia  River,  extending  into  British  Columbia,  Montana,  and  Utah,  also  south- 
ward in  a  wide-leaved  form  to  middle  Nevada  and  middle  eastern  California;  occurs 
mostly  as  scattered  plants  on  areas  where  subspecies  spedosus  is  more  abundant.  Type 
locality,  not  specifically  given,  but  probably  in  the  valley  of  the  Snake  River,  for  the 
habitat  of  C.  spedosus  is  given  by  Nuttall  as  "in  the  Rocky  Mountain  plains,  near 
Lewis'  River,"  and  albicaulis  is  then  described  as  a  form  of  this,  with  no  other  locality 
mentioned.  Collections:  Wawawai,  Washington,  Piper  1571  (Mo.  Bot.  Gard.);  Prosser, 
Yakima  Region,  Washington,  Cotton  897  (Gr) ;  near  forks  of  Cottonwood  Canon,  eastern 


C.    NAUSEOSUS.  213 

Oregon,  Leiberg  884  (Gr,  UC,  US);  Warm  Springs,  Cook  County,  Oregon,  Coville  and 
Applegate  7S4  (US);  Poison,  Montana,  Umbach  227  (NY);  Marysvale,  Utah,  Jones  5967 
(NY,  UC);  California:  Modoc  County,  near  the  Oregon  line,  Clements  and  Hall  11662 
(UC);  Big  Meadows,  August,  1880,  Austin  (Herb.  Greene,  type  of  C.  orthophyllus  Greene, 
minor  variation  63) ;  Honey  Lake  Valley,  Lassen  County,  Clements  and  Hall  11681  (UC) ; 
Truckee,  Nevada  County,  Heller  7192  (Gr,  NY,  UC,  minor  variation  25,  C.  calif ornicus 
Greene);  near  Bridgeport,  Mono  County,  Bolander  6159  (UC,  same  variation);  near 
Reno,  Nevada,  August,  1883,  Brandegee  (UC,  same  variation). 

12f.  Chrysothamnus  nauseosus  typicus. — Low  shrub  2  to  6  dm.  high,  woody  only 
at  the  base,  usually  rounded  and  not  as  broad  as  high,  often  nearly  prostrate;  twigs  mostly 
erect,  very  leafy,  not  striate,  gray  or  at  the  most  whitish  with  a  smooth  close  tomentum 
(white  in  minor  variation  64);  herbage  not  strongly  scented;  leaves  narrowly  linear,  2 
to  5  cm.  long,  0.5  to  1.5  mm.  wide,  either  spreading  or  ascending,  white-tomentose;  inflor- 
escence cymose  or  elongated;  involucre  6.5  to  8  mm.  high;  bracts  rather  obtuse,  scarcely 
keeled,  the  outer  ones  tomentulose  and  somewhat  glandular,  ciliolate  at  least  at  summit, 
the  innermost  only  puberulent  or  glabrous;  corolla  6.5  to  8  mm.  long  (9  mm.  in  one  col- 
lection); tube  puberulent,  rarely  arachnoid;  lobes  linear-lanceolate,  1.2  to  2  mm.  long; 
style-appendage  longer  than  the  stigmatic  part  or  sometimes  slightly  shorter;  achenes 
densely  pubescent.  {Chrysocoma  nauseosa  Pallas  in  Pursh,  Fl.  Am.  Sept.  2:517,  1814.) 
Assiniboia  and  Montana  to  South  Dakota,  Colorado,  Utah,  and  British  Columbia;  often 
on  bleak  or  alkaline  plains,  especially  common  in  Wyoming  and  eastern  Colorado.  Type 
locality,  on  the  banks  of  the  Missouri.  Collections:  Type  collection,  Lewis  (Phila,  see 
under  Chrysocoma  nauseosa,  p.  219;  Sedan,  Gallatin  County,  Montana,  August  12,  1902, 
W.  W.  Jones  (Gr,  UC) ;'  Great  Falls,  Montana,  Anderson  89  (UC)  f  Pennington  County, 
South  Dakota,  abundant  in  bad  lands.  Over  1804  (US);^  Douglas,  Converse  County, 
Wyoming,  Nelson  9001  {R,  UC);^  Howell  Lakes,  Wyoming,  Nelson  5315  (NY,  UC);' 
Laramie,  Wyoming,  July  29,  1889,  Greene  (Herb.  Greene,  UC,  US);'  Huttons  Lake, 
Wyoming,  Nelson  5300  (R,  Gr,  NY,  UC,  US,  type  collection  of  C.frigidus  concolor  Nelson, 
minor  variation  36) ;  near  Laramie,  Wyoming,  Nelson  5347  (R,  Gr,  NY,  type  collection  of 
C.  pallidus  Nelson,  minor  variation  64);  New  Windsor,  Weldon  County,  Colorado, 
Osterhout  2335  (NY,  R,  UC) ;'  near  Kanab,  Utah,  Jones  6047d  (US) ;'  Milk  River,  Assini- 
boia,  Macoun  10871    (US).' 

12^.  Chrysothamnus  nauseosus  salicifolius  (Rydberg). — Shrub  3  to  10  dm.  high, 
with  erect  branches;  twigs  erect  or  ascending,  very  leafy  to  the  summit,  plainly  striate, 
gray  with  a  thin  loose  tomentum  or  nearly  green;  herbage  probably  not  fragrant;  leaves 
broadly  linear,  4  to  8  cm.  long,  3  to  5  mm.  wide,  3-nerved,  minutely  tomentulose;  inflor- 
escence cymose,  dense;  involucre  7  to  8  mm.  high;  bracts  mostly  obtuse,  not  keeled, 
the  ranks  obscure,  the  outer  (more  acute)  ones  slightly  tomentulose,  the  inner  glabrous 
or  only  ciliate;  corolla  about  10  mm.  long,  tube  only  minutely  puberulent;  lobes  1.5  to  2 
mm.  long;  style-appendage  longer  than  the  stigmatic  portion;  achenes  densely  pubescent. 
(C.  salicifolius  Rydberg,  Bull.  Torr.  Club  37:130,  1910.)  Apparently  rare  and  confined 
to  Utah.  Type  locality.  Strawberry  Valley,  Utah.  Collections:  Type  collection,  2,150 
m.  altitude,  Leonard  288  (NY);  near  Salt  Lake  City,  Utah,  Garrett  2455  (NY);  Twelve- 
mile  Creek,  Utah,  Ward  659  (Gr). 

12/i.  Chrysothamnus  nauseosus  occidentalis  (Greene). — Shrub  probably  rather 
low,  with  numerous  short,  slender,  erect  branches;  twigs  ascending,  leafy,  striate,  gray- 
tomentose,  but  not  loosely  or  flocculently  so;  herbage  not  strongly  odorous;  leaves  nar- 
rowly linear,  4  cm.  or  less  long,  mostly  less  than  1  mm.  wide,  but  occasionally  up  to  3 


'  The  form  of  typicus  described  as  C.  frigidus  Greene,  minor  variation  35,  p.  220. 
•  The  form  of  lypicua  described  as  C.  platlensis  Greene,  minor  variation  67,  p.  222. 


214  GENUS   CHRYSOTHAMNUS. 

mm.,  1-nerved,  tomentulose;  inflorescence  compactly  cymose,  rounded,  2  to  5  cm.  across; 
involucre  7  to  10  mm.  high;  at  least  some  of  the  bracts  abruptly  acute  or  cuspidate, 
keeled,  5-rowed,  the  outer  ones  more  or  less  glandular-puberulent;  corolla  8.5  to  10.5  mm. 
long;  tube  only  puberulent;  lobes  lanceolate-linear,  about  2  mm.  long;  style-appendage 
longer  than  the  stigmatic  part;  achenes  densely  pubescent.  (C  californicus  var.  occi- 
dentahs  Greene,  Erythea  3:112,  1895,  in  part.  C.  occidentalis  Greene,  Fl.  Fran.  369, 
1897.)  Inner  Coast  Ranges  and  Sierra  Nevada  Mountains  of  California.  Type  local- 
ity, in  the  Coast  Ranges  of  California,  from  Humboldt  County  southward  and  in  the 
mountains  of  southern  California.  Collections:  Mount  Eddy,  Baker  3785  (UC);  Grouse 
Creek,  Humboldt  County,  August  2,  1888,  Chesnut  and  Drew  (UC);  South  YoUa  Bolla, 
October,  1916,  Merriam  and  Bailey  (UC);  Bloody  Canon,  Mono  County,  August  13, 
1898,  Congdon  (DS) ;  Kaweah  River  Basin,  Hopping  52  (UC) ;  Barton  Flats,  San  Bernar- 
dino Mountains,  Wilder  597  (UC) ;  Cleveland  National  Forest,  San  Jacinto  Mountains, 
de  Forest  129  (S.  F.  office,  U.  S.  Forest  Service). 

122.  Chrysothamnus  naxjseosus  bernardinus  (Hall). — Shrub  probably  low  and  with 
erect  stems  but  habit  not  well  known;  twigs  erect,  simple,  leafy,  not  striate,  coated  with 
a  smooth  gray  or  white  pannose  tomentum;  leaves  ascending,  linear,  very  acute,  often 
recurved  at  tip,  3  to  5  cm.  long,  1  to  2  mm.  wide,  mostly  conduplicate,  1-nerved,  green 
and  scabro-puberulent  ( white- tomentose  in  minor  variation  51);  inflorescence  a  loose 
rounded  cyme,  3  to  10  cm.  across,  the  lower  branches  2  to  10  cm.  long;  involucre  10  to  13 
mm.  high;  bracts  sharply  acuminate,  keeled,  in  well-defined  ranks,  glabrous  or  slightly 
erose-ciliate  or  the  outer  ones  obscurely  puberulent  (white-tomentose  in  minor  variation 
51);  corolla  9  to  12  mm.  long;  tube  sparsely  crisp-puberulent ;  lobes  linear-lanceolate, 
acute,  1.5  to  2.5  mm.  long;  style-appendage  longer  than  the  stigmatic  part;  achenes 
densely  sericeous-pubescent.  (C.  nauseosus  var.  bernardinus  Hall,  Univ.  Calif.  Publ. 
Bot.  7:171,  1919.)  Mountains  of  southern  California.  Type  locality,  hillsides  at  2,250 
m.  altitude,  Bluff  Lake,  San  Bernardino  Mountains,  California.  Collections:  Type  col- 
lection, September  2,  1905,  Grinnell  (UC);  open  pine  woods  near  Acton,  Los  Angeles 
County,  August  24,  1893  (DS,  ex  herb.  Hasse);  above  Aroyo  Seco,  West  Fork  Divide, 
San  Gabriel  Mountains,  September  4,  1915,  Grinnell  (SF);  Pine  Mountain  Ridge,  San 
Antonio  Mountains,  California,  Johnston  1652  (DS,  UC);  Round  Valley,  San  Jacinto 
Mountains,  California,  Hall  341  (UC,  form  with  very  compact  cymes  and  elongated 
anther-tips  and  style-appendages,  Hall,  1.  c). 

12j.  Chrysothamnus  nauseosus  graveolens  (Nuttall). — Shrub  commonly  6  to  15 
dm.  high,  robust,  taller  than  broad,  with  erect  branches;  twigs  erect,  leafy,  more  or  less 
evidently  striate,  yellowish-green  to  nearly  white  with  a  compact  smooth  tomentum; 
herbage  mildly  ill-scented;  leaves  broadly  linear,  4  to  6  cm.  long,  1  to  2  mm.  wide,  some 
of  them  usually  3-  or  5-nerved,  impunctate,  smooth  and  green  but  often  slightly  tomentu- 
lose, especially  beneath;  inflorescence  a  round  or  flat-topped  cyme,  fastigiate,  the  heads 
crowded,  involucre  6  to  8  mm.  high;  bracts  acute,  keeled,  in  rather  well-defined  vertical 
rows,  glabrous;  corolla  7  to  9  mm.  long;  tube  puberulent  or  glabrous;  lobes  0.5  to  1.5  mm. 
long,  erect;  style-appendage  longer  than  the  stigmatic  part;  achenes  densely  pubescent. 
{Chrysocoma  graveolens  Nuttall,  Genera  2: 136,  1818.)  On  plains  in  only  slightly  alkaline 
soil,  North  Dakota  to  Colorado,  New  Mexico,  northern  Arizona,  Utah,  and  Idaho.  Type 
locality,  on  the  banks  of  the  Missouri,  in  denuded  soils.  Collections:  Washington 
County,  North  Dakota,  August,  1886,  Hatcher  (UC);  Platte  Canon,  Wyoming,  Nelson 
8642  (Gr,  NY,  R,  UC);  Colorado:  New  Windsor,  Weldon  County,  Osterhout  2336  (NY, 
UC,  US);  west  of  Trinidad,  Hall  10777  (UC);  Canon  City,  September  7,  1896,  Greene 
(Herb.  Greene,  type  of  C.  virens  Greene,  minor  variation  79) ;  Grand  Junction,  August  27, 
1896,  Greene  (Herb.  Greene,  type  of  C.  laeievirens  Greene,  minor  variation  42);  Grand 


C.    NAUSEOSUS.  215 

Junction,  August  27,  1896,  Greene  (Herb.  Greene,  type  of  C.  falcatm  Greene,  minor  var- 
iation 33) ;  vicinity  of  Farmington,  New  Mexico,  Standleij  6884  (US) ;  Adamana,  Arizona, 
Hall  11164  (UC) ;  Green  River,  Utah,  Jones  516  (UC) ;  Sierra  La  Sal,  Utah,  Purpus  7071 
(UC);  mesa  west  of  Pocatello,  Idaho,  Eggleston  9936  (US). 

\2k.  Chrysothamnus  naxjseosus  pinifolius  (Greene). —  Shrub  of  medium  size  (6  to 
15  dm.  high),  taller  than  broad,  with  erect  branches;  twigs  slender,  erect,  leafy,  striate, 
green  with  a  closely  packed  tomentum  (rarely  white  and  non-striate) ;  herbage  with  a 
disagreeable  odor;  leaves  linear-filiform,  3.5  to  6  cm.  long,  1  mm.  or  less  wide,  1-nerved, 
green  to  grayish  puberulent,  often  densely  tomentulose  beneath;  inflorescence  a  thyrsoid 
panicle  of  rounded  or  pyramidal  outline,  varying  to  short-oblong;  involucre  6  to  8  or 
rarely  9  mm.  long;  bracts  acute,  keeled,  in  vertical  rows,  glabrous;  corolla  6.5  to  9  mm. 
long;  tube  puberulent  or  glabrous;  lobes  0.5  to  1  mm.  long;  style-appendage  longer  than 
stigmatic  part;  achenes  densely  pubescent.  (C.  pinifolius  Greene,  Pittonia  5:60,  1902.) 
Alkaline  plains  and  plateaus,  Colorado,  New  Mexico  (and  Utah?).  Type  locality, 
Gunnison,  Colorado.  Collections:  Type  collection,  September  1,  1896,  Greene  (Herb. 
Greene) ;  Alamosa,  San  Luis  Valley,  Colorado,  Hall  10784a  (UC) ;  lola,  region  of  the  Gun- 
nison watershed.  Baker  668  (Gr,  NY,  US) ;  Doyles,  west  central  Colorado,  Baker  629  (Gr, 
NY,  UC,  US,  twigs  green  in  one  specimen,  white  in  another) ;  above  Datil,  New  Mexico, 
Wooton  2494  (DS,  Gr,  NY,  UC);  White  Mountains,  Lincoln  County,  New  Mexico, 
Wooion  379  (Gr,  Greene,  UC,  US,  type  collection  of  C.  confinis,  minor  variation  30). 

12/.  Chrysothamnus  nauseosus  consimilis  (Greene). — Shrub  commonly  6  to  15  dm. 
high,  taller  than  broad,  with  erect  branches;  twigs  erect,  very  leafy,  striate,  green,  with  a 
closely  packed  tomentum;  herbage  with  a  strong  disagreeable  odor;  leaves  nearly  filiform, 
2.5  to  5  mm.  long,  less  than  1  mm.  wide,  1-nerved,  somewhat  resinous  and  canescently 
tomentulose  to  nearly  glabrous;  inflorescence  an  elongated  pyramidal  or  cylindric  thyrsus; 
involucre  7  to  8  mm.  high;  bracts  acute,  keeled,  in  fairly  distinct  vertical  rows,  glabrous; 
corolla  7  to  8.5  mm.  long;  tube  glabrous  or  only  puberulent;  lobes  linear,  1  to  2  mm.  long, 
spreading  in  age;  style-appendages  longer  than  the  stigmatic  part;  achenes  densely 
pubescent.  (C.  consirnilis  Greene,  Pittonia  5:60,  1902.)  Alkaline  valleys  and  plains, 
western  Wyoming  and  Colorado  to  New  Mexico,  northern  Arizona,  Nevada,  northeast- 
ern California  (and  one  collection  from  San  Diego  County),  eastern  Oregon,  and  Idaho. 
Type  locality,  Deeth,  Elko  County,  Nevada.  Collections:  Evanston,  Wyoming,  Nelson 
4105  (Gr,  NY,  R,  UC,  US,  type  collection  of  C.  oreophilus  Nelson,  minor  variation  61); 
Marysvale,  Utah,  Jones  5966  (UC,  US) ;  Tooele  Valley,  Utah,  Jones  502  (UC) ;  eastern 
base  San  Francisco  Mountains,  Arizona,  Hall  11180  (UC);  type,  August  7,  1895,  Greene 
(Herb.  Greene);  Goldfield,  Nevada,  Hall  10808  (UC);  Fallon,  Nevada,  Heller  10679 
(DS,  Gr,  NY,  UC,  US);  California:  Tantillas  Mountains,  San  Diego  County,  1875, 
Palmer  (Gr) ;  Bridgeport,  Mono  County,  Hall  10866  (UC) ;  Shasta  Valley,  Heller  12978 
(DS,  SF,  UC);  near  Alturas,  Modoc  County,  1894,  Austin  (Herb.  Greene,  type  of  C. 
angustus,  minor  variation  21);  Lake  County,  Oregon,  Leiberg  769  (UC);  Boise,  Idaho, 
Clark  317  (Gr,  NY,  UC,  US,  type  collection  of  C.  oreophilus  artus  Nelson,  minor 
variation  62). 

12to.  Chrysothamnus  nauseosus  viridulus  (Hall). — Shrub  5  to  20  or  even  30  dm. 
high,  robust,  taller  than  broad,  with  ascending  branches;  twigs  erect,  leafy,  rather  stout, 
striate,  densely  covered  with  pannose  yellowish-green  smooth  tomentum;  herbage  mal- 
odorus;  leaves  (at  first  erect  or  ascending,  later  inclined  to  droop)  narrowly  linear,  acute, 
3  to  5  cm.  long,  about  1  mm.  wide,  1-nerved,  channeled  above,  green  but  tomentulose  on 
both  sides;  inflorescence  a  pyramidal  to  nearly  globose  thyrse;  involucre  6.5  to  8.5  mm. 
high ;  bracts  acute  except  the  obtuse  inner  ones,  keeled,  in  5  vertical  ranks,  glabrous  but 
viscid  with  a  resinous  exudation;  corolla  7  to  9.5  mm.  long;  tube  glabrous  or  sparsely 


216  GENUS   CHRYSOTHAMNUS. 

puberulent;  lobes  1.7  to  2.5  mm.  long,  recurving  in  age;  style-appendage  longer  than 
the  stigmatic  part;  achenes  densely  sericeous.  (C  nauseosus  var.  viridulus  Hall,  Univ. 
Calif.  Publ.  Bot.  7:177,  1919.)  Alkaline  flats  of  west  central  Nevada  and  in  eastern 
California,  from  Mono  County  south  to  the  desert  side  of  the  San  Antonio  Mountains. 
Type  locality,  Benton,  Mono  County,  California,  on  sandy  alkaline  flats  with  DistichKs, 
at  1,720  m.  altitude.  Collections:  Lida,  Esmeralda  County,  Nevada,  Hall  1081  i 
(UC);  California:  north  side  Mono  Lake,  Hall  10846  (UC);  type  collection,  November  3, 
1917,  Hall  10642  (UC) ;  Antelope  Valley,  Hall  10580  and  10582  (UC,  minor  variation  59); 
San  Antonio  Mountains,  Johnston  1706  (UC) ;  east  of  Bear  Valley,  San  Bernardino  Moun- 
tains, August  20,  1907,  Bailey  (UC);  and  a  large  series  mostly  from  Owens  Valley,  in 
Univ.  Calif.   Herb. 

12n.  Chrysothamnus  nauseosus  ceruminosus  (Durand  and  Hilgard). — Shrub  5 
to  12  dm.  high,  rounded,  fastigiately  branched;  twigs  erect,  short-leafy,  striate,  yellowish- 
green  with  a  smooth  compact  tomentum;  herbage  scarcely  odorous;  leaves  linear-filiform, 
1  to  3  cm.  long,  less  than  1  mm.  wide,  1-nerved,  tomentulose;  inflorescence  compactly 
cymose,  rounded,  2  to  3  cm.  across;  involucre  7  to  8  mm.  high;  bracts  abruptly  narrowed 
to  a  filiform  recurved  mucro  about  1  mm.  long,  keeled,  somewhat  ranked,  glabrous  and 
glutinous;  corolla  about  6.5  mm.  long;  tube  puberulent;  lobes  1.5  to  2.0  mm.  long; 
style-appendages  longer  than  the  stigmatic  part ;  achenes  densely  pubescent.  {Linosyris 
ceruminosa  Durand  and  Hilgard,  Jour.  Acad.  Nat.  Sci.  Phila.  II,  3:40,  1855;  also  Pacif. 
R.  R.  Rep.  3:9,  plate  6,  1857.)  Mojave  Desert,  California,  and  mountains  to  the  west. 
Type  locality,  Tejon  Pass,  California.  Collections:  Type  collection,  September,  1853, 
Heermann  (Or,  US);  Hesperia,  California,  October,  1917,  Spencer  (UC). 

12o.  Chrysothamnus  nauseosus  mohavensis  (Greene). — Shrub  of  medium  or  large 
size,  usually  8  to  16  dm.  high  and  with  elongated  straight  stems;  twigs  erect  or  ascending, 
often  but  not  always  nearly  leafless  and  rushlike,  striate,  white  or  greenish-yellow ;  leaves 
filiform,  very  acute,  2  to  3  cm.  long,  1-nerved,  nearly  glabrous;  inflorescence  a  rounded 
or  somewhat  elongated  thyrse;  involucre  narrow,  9  to  10.5  mm.  long;  bracts  obtuse  to 
acute,  sharply  keeled,  in  very  distinct  vertical  ranks,  glabrous;  corolla  8  to  10  mm.  long; 
tube  puberulent;  lobes  1.5  to  2.5  mm.  long,  spreading;  style-appendage  longer  than 
the  stigmatic  part;  achenes  densely  pubescent.  (Bigelovia  mohavensis  Greene  in  Gray, 
Syn.  Fl.  P:138,  1884.)  In  well-drained,  scarcely  alkaline  soil,  western  part  of  the 
Mojave  Desert,  north  in  the  inner  Coast  Ranges  to  Mount  Hamilton,  all  in  California. 
Type  locality,  Mojave  Desert,  California.  Collections:  Mojave  Desert,  July,  1884, 
Brandegee  (UC);  Oak  Creek,  south  of  Mojave,  Hall  10570  (UC,  flowering  twigs  leafless 
for  6  to  7.5  dm.);  near  Fort  Tejon,  1,550  m.  altitude,  Rothrock  271  (Gr);  Mojave  Desert, 
October  19,  1882,  Pringle  (Gr,  US);  Alamo  Mountain,  Ventura  County,  Baldwin  102 
(UC);  Rock  Creek,  desert  slopes  of  San  Gabriel  Mountains,  Abrams  and  McGregor  625 
(DS);  Priest  Valley  to  Coalinga,  San  Benito  County,  Abrams  7685  (DS);  Mount  Hamil- 
ton, Hall  9894  (UC). 

12p.  Chrysothamnus  nauseosus  junceus  (Greene). — Shrub  of  unknown  size,  strict, 
fastigiately  much  branched;  twigs  slender,  rush-like,  mostly  leafless,  not  striate,  yellow- 
ish-green with  a  smooth  compact  tomentum;  leaves  linear-filiform;  inflorescence  fastigi- 
ate-cymose;  involucre  about  10  mm.  high;  bracts  acute,  5  in  each  of  the  distinct  vertical 
rows,  glabrous;  corolla  about  9  mm.  long;  tube  pubescent  but  not  arachnoid;  lobes  about 
1.5  mm.  long,  externally  beset  with  long  delicate  hairs;  style-appendage  longer  than  the 
stigmatic  part;  achenes  densely  pubescent.  {Bigelovia  juncea  Greene,  Bot.  Gaz.  6:184, 
1881.)  Known  only  from  Arizona.  Type  locality,  calcareous  bluffs  of  the  Gila  River  in 
eastern  Arizona,  very  near  the  New  Mexican  boundary.  Collections:  Type  collections, 
September  5,  1880,  Greene  (Gr,  Jones,  hairs  on  corolla-lobes  wanting  or  deciduous  in 


C.    NAUSEOSUS,  217 

specimen  in  Herb.  Jones) ;  same  locality,  October  29,  1880,  Greene  (NY) ;  Bright  Angel 
Trail,  Grand  Canon,  Arizona,  Eastwood  370S  (SF). 

\2q.  Chrysothamnus  nauseosus  turbinatus  (Jones). —  Shrub  5  to  15  dm.  high, 
rounded,  bushy,  broader  than  high;  twigs  irregularly  ascending,  leafy,  faintly  striate, 
yellowish-green  with  a  close,  smooth  tomentum;  herbage  not  strongly  scented;  leaves 
linear,  1.5  to  2.5  cm.  long,  about  1  mm.  wide,  1 -nerved,  merely  tomentulose  to  densely 
white-tomentose;  inflorescence  a  few-headed  simple  or  compound  cyme;  involucre  9  to 
11  mm.  high,  very  narrow,  cylindric;  bracts  obtuse,  often  shortly  apiculate,  not  keeled, 
4  or  5  in  each  vertical  row,  sparsely  tomentulose  or  the  inner  ones  only  ciliate;  corolla 
10  to  11  mm.  long;  tube  puberulent;  lobes  ovate,  erect,  scarcely  over  0.5  mm.  long,  the 
tips  villous  with  long  hairs;  style-appendage  longer  than  the  stigmatic  part;  achenes 
densely  pubescent.  (Bigelovia  turbinata  Jones,  Proc.  Calif.  Acad.  II,  5:691,  1895.)  In 
mounds  of  clay  or  sandy  soil  built  up  in  alkaline  flats,  southern  Utah.  Type  locality, 
Canaan  Ranch  (near  Kanab,  Kane  County),  Utah,  on  clay  soil  on  the  borders  of  an  old 
sink,  at  1,540  m.  altitude.  Collections:  Type  collection,  September  24,  1894,  Jones 
(Herb.  Jones) ;  Champlain,  August  14,  1911,  Jones  (DS,  Herb.  Jones) ;  Lund,  Iron  County, 
Hall  10786  (UC). 

12r.  Chrysothamnus  nauseosus  glareosus  (Jones). — Shrub  said  to  be  only  about 
3  dm.  high,  many-stemmed;  twigs  erect,  sparsely  leafy;  leaves  broadly  to  narrowly  linear, 
slightly  widened  above,  plane;  inflorescence  cymose;  involucre  about  11  mm.  high; 
bracts  obtuse,  somewhat  keeled,  in  obvious  ranks,  erose-ciliate,  scurfy-tomentulose ; 
corolla  10  to  12  mm.  long,  glabrous;  lobes  linear-lanceolate;  style-appendage  longer  than 
the  stigmatic  part,  0.9  mm.  long;  achenes  glabrous.  {Bigelovia  glareosa  Jones,  Zoe  2:247, 
1891.)  Gravelly  mesas  of  central  and  southern  Utah  and  northern  Arizona.  Type 
locality,  Marysvale,  southern  Utah.  Collections:  Little  Colorado  River,  Arizona,  Octo- 
ber 8,  1851,  Thurber  (?)  (Gr). 

12s.  Chrysothamnus  nauseosus  bigelovi  (Gray). — Shrub  3  to  10  dm.  high,  densely 
branched;  twigs  short,  erect,  leafy  or  nearly  leafless,  striate,  yellowish-green  with  a  closely 
packed  smooth  tomentum;  herbage  scarcely  odorous;  leaves  linear-filiform,  1  to  2.5  cm. 
long,  0.5  to  1  mm.  wide,  1-nerved,  tomentulose  when  young;  inflorescence  a  lax  few- 
headed  cyme  terminating  each  of  the  branches;  involucre  10  to  11.5  mm.  high;  bracts 
acute  or  subacuminate,  spreading  in  age,  4  or  5  in  each  row,  tomentulose  and  sometimes 
ciliate;  corolla  9  to  10  mm.  long;  tube  glabrous  or  nearly  so;  lobes  ovate,  erect  or  spread- 
ing, 0.8  to  1.5  mm.  long;  style-appendage  longer  than  the  stigmatic  part;  achenes  glabrous, 
5-nerved.  {Linosyris  (Chrysothamnus)  bigelovi  Gray,  Pacif.  R.  R.  Rep.  4^:98,  plate  12, 
1857.)  On  very  dry  hills  and  plains,  southern  Colorado  to  Texas  and  Arizona.  Type 
locality,  hills  and  arroyos,  Cienegella,  above  Albuquerque,  New  Mexico.  Collections: 
Buena  Vista,  Colorado,  Crandall  2735  (NY,  US) ;  Wet  Mountain  Valley,  Colorado,  Au- 
gust 29,  1893,  Brandegee  (UC) ;  Colfax,  Colorado,  October,  1877,  Brandegee  (UC) ;  type 
collection,  1853-54,  Bigelow  (Gr);  south  of  Farmington,  New  Mexico,  Hall  III40  (UC, 
form  with  villous  corolla-lobes) ;  badlands  near  Ojo  Alamo,  New  Mexico,  Hall  11137 
(UC);  Las  Palomas,  Sandia  Mountains,  New  Mexico,  Ellis  319  (NY,  US);  Painted  Des- 
ert, Arizona,  October,  1919,  Long  (UC,  intermediate  to  subspecies  glareosus,  the  bracts 
only  acute);  Navajo  Indian  Reservation,  Arizona,  Standley  7373  (Gr,  NY,  UC,  US); 
Moqui  Indian  Reservation,  Arizona,  August  22,  1897,  Zuck  (Herb.  Greene,  type  of  C. 
moquianus  Greene,  minor  variation  47). 

\2t.  Chrysothamnus  nauseosus  leiospermus  (Gray). — Shrub  low  (3  to  12  dm.  high), 
with  erect  branches ;  twigs  very  many,  crowded,  erect,  either  moderately  leafy  or  almost 
naked,  scarcely  at  all  striate,  yellowish-green  to  white  even  on  the  same  twigs  (type) 


218  GENUS    CHRYSOTHAMNUS. 

with  a  very  close  tomentum;  herbage  not  noticeably  odorous;  leaves  filiform  or  nearly  so, 
acute,  mostly  0.5  to  2  or  3  cm.  long,  under  0.5  mm.  wide,  often  reduced  and  scale-like,  to- 
mentose  or  green  and  essentially  glabrous;  inflorescence  a  close  terminal  cyme  of  2  or  3 
cm.  diameter;  involucre  6  to  8  mm.  high;  bracts  obtuse,  not  keeled,  in  vague  ranks,  gla- 
brous; corolla  5  to  8  mm.  long;  tube  very  obscurely  pubescent  (or  glabrous?) ;  lobes  ovate, 
erect,  0.5  mm.  or  less  long;  style-appendage  longer  than  the  stigmatic  part;  achenes  com- 
pletely glabrous  in  the  tj^jical  form  but  often  sparsely  pubescent,  especially  along  the 
prominent  nerves.  {Bigelovia  leiosperma  Gray,  Syn.  Fl.  P,  139,  1884.)  On  exceedingly 
arid  slopes,  southern  Utah,  southern  Nevada,  and  the  borders  of  California.  Type 
locality,  Saint  George,  southwestern  Utah.  Collections:  Tjrpe  collection,  1875,  Palmer 
(Gr);  southeastern  Utah,  Rydberg  and  Garrett  9435,  9940,  both  with  bracts  nearly  as 
acute  as  in  subspecies  bigelovi  but  not  pubescent  (UC,  US) ;  Clear  Creek  Canon,  Utah, 
Jones  6105  (Herb.  Jones,  NY,  UC,  type  collection  of  Bigelovia  leiosperma  abbreviata  Jones, 
minor  variation  14);  3  miles  north  of  Salina,  Utah,  Jones  529  (UC,  same  variation); 
Panaca,  Nevada,  September  5,  1912,  Jones  (UC);  Caliente,  Nevada,  Hall  10791,  10795 
(UC);  Candelaria,  Nevada,  Shockley  311  (DS,  Gr);  Providence  Mountains,  California, 
June  6,    1902,   Brandegee. 

MINOR  VARIATIONS  AND  SYNONYMS. 

The  number  of  minor  variations  of  Chrysothamnus  nauseosus  is  exceptionally  high.  This  list  includes  only 
those  which  have  already  received  names  and  a  few  others  of  exceptional  interest.  StOl  smaller  variations, 
many  of  which,  however,  are  more  significant  than  some  of  the  named  species  of  preceding  taxonomists.  have 
been  indicated  by  parenthetical  remarks  in  the  citation  of  specimens  under  the  subspecies  or  are  left  without 
mention.  To  list  and  describe  all  of  these  would  occupy  much  space  and  would  be  of  little  value,  unless 
accompanied  by  a  close  ecologic  and  genetic  analysis. 

AU  of  the  kno\vn  synonyms  under  Bigelovia,  Chrysocoma,  Chrysothamnus,  and  Linosyris  are  here  listed. 
The  few  that  have  been  published  under  other  genera  are  not  of  significance,  since  none  of  them  take  prece- 
dence over  the  names  here  given. 

1.  Bigelovia  bigelovi  Gray,  Proc.  Am.  Acad.  8:642,  1873.— C.  nauseosus  bigelovi. 

2.  B.  CERUMINOSA  Gray,  1.  c.  643,  1873.— C.  nauseosus  ceruminosus. 

3.  B.  COLLINA  Nelson,  Wyo.  Exp.  Sta.  Bull.  28:122,  1896.— Based  upon  C.  collinus  Greene,  which  see. 

4.  B.  DEAcu^•cULOIDES  DeCandolle,  Prodr.  5:329,  1836.— C.  nauseosus  graveolens.  DeCandoUe  here  makes 
a  transfer  of  the  specific  name  from  Chrysocoma  dracunculoides  Pursh  (Fl.  Am.  Sept.  2:517,  1814).  Pursh's 
description  was  intended  to  include  graveolens,  although  the  reference  to  Chrysocoma  dracunculoides  Lamarck 
is  an  error,  Lamarck's  plant  being  an  Aster. 

5.  B.  GLAREOSA  Joucs,  Zoe  2:247,  1891. — C.  nauseosus  glareosus. 

6.  B.  GRAVEOLENS  Gray,  Proc.  Am.  Acad.  8:644,  1873. — C.  nauseosus  graveolens,  in  part.  Several  of  the 
cited  synonyms  belong  to  other  subspecies. 

7.  B.  GRAVEOLENS  var.  ALBiCAULis  Gray,  1.  c.  645,  1873. — C.  nauseosus  albicaulis. 

8.  B.  GRAVEOLENS  var.  appendiculata  Eastwood,  Proc.  Calif.  Acad.  Ill,  1:74,  plate  6,  1897.- An 
abnormal  form  of  C.  tiauseosus  latisquamevs,  wth  1  to  4  linear  appendages  on  the  corolla-tube.  The  tube  is 
arachnoid-pubescent  and  the  lobes  are  very  short,  these  characters  suggesting  a  connection  with  subsp.  holo- 
leucus.     Type  locality,  White  Sands  of  New  Mexico. 

9.  B.  GRAVEOLENS  var.  glabrata  Gray,  Proc.  Am.  Acad.  8:645,  1873.— C.  nauseosus  graveolens,  from  the 
description,  although  this  appUes  also  to  several  other  subspecies.  The  synonym  cited  has  not  been  placed. 
(See  No.  83  of  this  list.) 

10.  B.  graveolens  var.  hololeuca  Gray,  Proc.  Am.  Acad.  8:645,  1873.— C.  nauseosus  hololeucus. 

11.  B.  graveolens  var.  latisquamea  Gray,  Proc.  Am.  Acad.  8:645,  1873.— C.  nauseosus  latisquameus. 

12.  B.  juncea  Greene,  Bot.  Gaz.  6:184,  1881.- C.  nauseosus  junceus. 

13.  B.  leiosperma  Gray,  Syn.  Fl.  1«:139,  1884.— C.  nauseosus  leiospermus. 

14.  B.  leiosperma  var.  abbreviata  Jones,  Proc.  Calif.  Acad.  11,  5:693,  1895.— C.  nauseosus  leiospermus, 
but  %\ith  scant  tomentum  and  wth  leaves  1  cm.  or  less  long.     The  type  is  from  Clear  Creek,  Utah. 

15.  B.  missouriensis  DeCandolle,  Prodr.  5:329,  1836.— Based  upon  Chrysocoma  nauseosa  Pallas;  there- 
fore the  same  as  Chrysothamnus  nauseosus  tijpicus. 

16.  B.  MOHAVENSia  Greene  in  Gray,  Syn.  Fl.  l':138,  1884.— C.  nauseosus  mohavensis. 

17.  B.  turbinata  Jones,  Proc.  Calif.  Acad.  II,  5:691,  1895.— C.  nauseosus  turhinaius. 


C.    NAUSEOSUS.  219 

18.  Chrysocoma  dracunculoides  Lamarck,  Encyl.  2:192,  1790. — The  description  is  that  of  an  Aster,  bu- 
the  name  was  later  taken  up  by  Pursh  (Fl.  Am.  Sept.  2:517,  1814),  who  included  under  it  a  form  of  Chrysot 
thamnus  naiiseosus,  probably  subspecies  graveolens. 

19.  C.  GH.WEOLENS  Nuttall,  Genera  2:136,  1818. — Chrysolhamnus  nauseosus  graveolens. 

20.  C.  NAUSEOSA  Pallas,  in  Pursh,  Fl.  Am.  Sept.  2:517,  1814. — Chrysothamnus  nauseosus  typicus.  There  is 
much  misunderstanding  as  to  the  form  that  Pallas  had  in  hand  when  his  description  was  drawn.  It  is  more  than 
probable  that  an  early  mixing  of  labels  of  the  Lewis  and  Clark  collection  is  responsible  for  this.  Although 
the  type  locality  is  stated  by  Pursh  as  "on  the  banks  of  the  Missouri,"  the  sheet  at  the  Philadelphia  Academy 
commonly  taken  as  the  type  is  labeled  "  15th  October  1805  on  the  Columbia  River."  Because  of  this,  nauseosus 
in  the  strict  sense  has  been  applied  to  a  form  most  common  in  the  Columbia  River  Basin  (subspecies  albicaulis). 
However,  the  two  specimens  on  the  sheet  referred  to  are  not  like  forms  that  grow  on  the  Columbia.  One, 
with  glabrous  in^•olucrcs,  long  style-appendages,  and  green  herbage,  is  one  of  the  graveolens  group  and  may  be 
ignored;  the  other,  mounted  on  the  right-hand  side  of  the  sheet,  has  gray-tomentose  herbage  and  involucres  and 
is  now  identified  with  "C.  frigidus,"  that  is,  subspecies  typicus  of  the  Missouri  River  region,  the  corolla  being 
too  short  (7  to  7.8  mm.)  for  albicaulis.  This  right-hand  piece  probably  is  a  part  of  the  type  collection,  but  for- 
tunately the  identification  of  Chrysocoma  nauseosa  need  not  depend  upon  this  sheet.  There  is  another  in  the 
PhOadelphia  Academy  labeled  "Chrysocoma  nauseosa  Pall.  Missouri,  Octbr."  "Pursh's  spec."  "Herb.: 
Lewis  &  Clark."  This  specimen  has  been  carefully  examined  by  the  present  author  and  found  to  agree  in  every 
detail  with  Pallas's  description,  except  that  the  innermost  bracts  are  faintly  pubescent  instead  of  glabrous — a 
difference  easily  overlooked  by  one  working  wthout  a  magnifying  glass.  Mr.  Bayard  Long,  of  the  Philadelphia 
Academy  Herbarium,  has  kindly  indicated  evidence  which  shows  almost  certainly  that  tliis  sheet  came  from  the 
Lambert  Herbarium,  where  Pursh's  types  were  deposited.  For  example,  the  paper  is  ^'ery  old  and  thin,  and 
the  data  originally  written  on  the  back  have  been  cut  off  and  pa.=ted  on  the  front  below  the  specimen,  these 
features  agreeing  exactly  with  those  of  other  specimens  well  known  to  have  come  from  the  Lambert  Herbarium. 
Furthermore,  the  Lambert  plants  were  distributed  through  the  general  Academy  herbarium  at  Philadelphia 
and  it  was  here  that  this  "Alissouri,  Octbr."  sheet  was  found,  while  the  other  was  segregated  in  the  "Lewis  and 
Clark  Herbarium"  and  therefore  came  from  the  American  Philosophical  Society,  not  from  Lambert.' 

The  conclusion,  therefore,  is  that  the  plant  labeled  "Columbia  River"  probably  came  from  the  Missouri 
and  that  the  right-hand  specimen  on  the  sheet  is  a  part  of  the  type  collection;  but  that  the  true  type  is  on  the 
other  sheet,  that  is,  the  one  labeled  "Missouri,  Octbr."  This  brings  both  the  locality  and  the  plant  into  agree- 
ment with  Pallas's  description.  The  type  as  thus  identified  is  a  plant  with  ascending  and  rather  straight  leaves 
and  minutely  pubescent  inner  bracts,  a  form  very  common  on  the  Missouri  drainage,  especially  in  Wyoming. 
C.  frigidus  Greene  is  exactly  the  same  thing  and  C.  plattensis  Greene  differs  by  characters  so  variable  that  it  is 
included  in  Chrysothamnus  naiiseosus  typicus. 

21.  Chrysothamnus  angustus  Greene,  Pittonia  5:64,  1902. — C.  nauseosus  consimilis.  Described  as  dis- 
tinguishable by  its  canescent  wooUiness.  but  more  abundant  material  proves  that  this  character  is  exceedingly 
variable  and  can  not  be  correlated  with  others  nor  with  geographic  distribution.  The  leaves  in  the  type  speci- 
men are  5  to  6  mm.  long,  very  slender  and  lax,  and  the  inflorescence  is  elongated.  .AJl  of  these  features  occur 
also  in  the  type  of  consimilis,  except  that  the  inflorescence  in  this  is  shorter.  The  type  specimens  of  these 
two  e.xhibit  no  differences  in  involucre  and  only  shght  variations  in  detail  of  floral  structure.  Type  locality, 
sagebrush  plains  north  of  Alturas,  Modoc  County,  California.     The  plants  no  doubt  came  from  alkaline  soil. 

22.  C.  APPENDICULATUS  Hcllcr,  Mulilenbergia  1:6,  1900. — C.  nauseosus  latisquameus.  (See  note  under 
Bigelovia  graveolens  appendiculata.) 

23.  C.  ARizoNicus  Greene,  Pittonia  4:42,  1899. — Based  upon  C.  speciosus  arizonicus  Greene,  which  see. 

24.  C.  BiGELOVi  Greene.  Erj-thea  3:112,  1895. — C.  nauseosus  bigelovi. 

25.  C.  CALiFORNicus  Greene,  1.  c,  111,  1895. — Here  taken  as  a  more  southerly  large-leaved  form  of  C.  nau- 
seosus albicaulis.  No  type  specimen  was  indicated,  but  Greene's  notations  at  the  University  of  California  leave 
no  doubt  that  the  form  represented  by  Bolander's  6159  from  near  Bridgeport,  Mono  County,  California,  were 
intended.  These  are  stout  plants  with  hea\-y  leaves  2  to  4  mm.  wide,  and  corolla-tubes  only  short-hairy.  They 
connect  with  albicaulis  through  forms  with  similar  leaves  but  arachnoid  corolla-tubes  {Heller  7192),  and  others 
with  slightly  narrower  leaves,  the  corolla-tubes  sparsely  arachnoid  or  only  puberulent  {Hall  10S5S),  and  still 
others  with  leaves  only  1  to  2  mm.  wide  and  the  corolla-tube  not  at  all  arachnoid  {Hall  11662).  The  wide- 
leaved  plants  of  californicus  so  closely  resemble  those  of  subspecies  speciosus  as  it  grows  in  the  same  district 
that  their  origin  from  this  rather  than  from  albicaulis  is  strongly  suggested  (see  minor  variation  58).  Collec- 
tions of  the  broad-leaved  variation  of  speciosus  (No.  58)  have  been  labeled  in  herbaria  by  Greene  as  cali- 
fornicus, and  he  doubtless  included  this  variation  in  his  conception  of  liis  species,  at  least  in  later  years. 

26.  C.  CALIFORNICUS  var.  occidentalis  Greene,  1.  c,  112,  1895. — C.  nauseosus  occidentalis. 

'  It  might  be  thought  that  the  type  specimen  was  sent  to  the  British  Museum  of  Natural  History,  but  it  is  learned  through 
the  kindness  of  Dr.  Rendle  that  no  authentic  material  of  Chrysocoma  nauseosa  is  to  be  found  there. 


220  GENUS   CHRYSOTHAMNUS. 

27.  C.  CERUMINOSUS  Greene,  1.  c,  94,  1895. — C.  nmtseosus  ceruminosvs. 

28.  C.  COLLINUS  Greene,  Pittonia  3 :  24,  1896. — A  variation  of  C.  nauseosus  typicus  in  which  the  inflorescence 
is  reduced  and  the  bracts  are  exceptionally  acute.  Described  as  "not  tomentose,  only  obscurely  cinereous  and 
notably  gummy."  The  type  in  the  Greene  Herbarium  has  the  tvngs  heavily  coated  vnih  a  compact  tomentum, 
as  in  all  of  the  subspecies.     Type  locality.  Rock  Springs,  Wyoming. 

29.  C.  CONCOLOR  Rydberg,  Fl.  Rocky  Mts.  856,  1917. — Based  upon  C.frigidus  concolor,  which  see. 

30.  C.  CONFIMS  Greene,  Pittonia  5:62,  1902. — Here  regarded  as  a  southern  variation  of  C.  nauseosus  pini- 
folius,  notwthstanding  its  short-ciliate  bracts  (described  as  obtuse  but  decidedly  acute  in  specimens  of  the  type 
collection)  and  its  occasionally  longer  heads.     Type  locality,  White  Mountains  of  southern  New  Mexico. 

31.  C.  coNSiMiLis  Greene,  Pittonia  5:60,  1902. — C.  nauseosus  consimilis. 

32.  C.  DRACUNCULoiDEs  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:324,  1840. — Based  upon  Bigelovia  dracuncu- 
loides,  which  see. 

33.  C.  FALCATUs  Greene,  1.  c,  62, 1902. — C.  nauseosus  pinifolius  with  the  twigs  and  upper  (not  lower)  surface 
of  the  leaves  coated  with  a  white  tomentum,  which  is  deciduous  in  places.  Other  differentiating  characters 
have  been  studied  by  Hall  and  found  to  be  of  no  moment  (Univ.  Calif.  Publ.  Bot.  7: 176,  1919).  Type  locality, 
plains  about  Grand  Junction,  Colorado. 

34.  C.  FORMO.SUS  Greene,  Pittonia  4:41,  1899.— Payson,  Bot.  Gaz.  60,  381,  1915.  Very  close  to  C.  nauseosus 
albicaidis  and  probably  to  be  accepted  as  a  minor  variation  of  this,  although  perhaps  derived  locally  from  sub- 
species speciosus,  as  albicaidis  is  supposed  to  have  been  elsewhere.  Known  only  from  Naturita,  southwestern 
Colorado.  A  low,  matted,  white  shrub  with  narrow  spreading  leaves,  the  involucres  10  mm.  long  and  with  4 
to  6  bracts  in  each  row,  the  outer  bracts  puberulent.  Type  coDected  by  Greene,  August  27,  1896  (Herb. 
Greene  26614).     Additional  collection,  Payson  605  (Gr,  St.  Louis). 

35.  C.  FRiGiDus  Greene,  Erythea  3: 112,  1895. — In  describing  this,  Greene  did  not  indicate  a  type  specimen, 
but  his  reference  to  its  abundance  about  Laramie,  Wyoming,  leads  to  the  assumption  that  specimens  there 
collected  by  him  July  29,  1889,  and  labeled  by  him  as  frigidtis  are  the  ones  from  which  the  description  was 
drawn.  These  specimens  are  now  in  the  Greene  Herbarium  and  in  the  University  of  California,  where  Greene 
was  working  at  the  time.  The  evidence  from  these  sheets  and  from  the  description  leaves  no  doubt  that  C. 
frigidus  is  the  same  as  C.  nauseosus  typicus.  In  fact,  Greene  himself  suggested  this  possibility.  A  slightly 
different  form,  described  by  Greene  as  C.  speciosus  var.(?)  platteyisis  and  later  raised  to  specific  rank,  is  now  also 
included  in  typicus.  This  differs  horn  frigidus  in  having  a  lax  foliage,  the  leaves  spreading  or  recurved  and  the 
bracts  glabrous  except  along  the  margins.  Both  forms  are  common  on  the  Rocky  Mountain  plains,  but  their 
separation  taxonomically  is  almost  impossible.  The  inner  bracts  even  in  frigidus  are  never  very  pubescent  and 
most  specimens  necessarily  referred  here  because  of  their  straight,  ascending  leaves,  have  the  bracts  exactly  as  in 
plattensis,  that  is,  pubescent  only  on  the  margins,  or  the  short  outermost  ones  slightly  pubescent  also  on  the  back 
(for  example,  Goodding  19SS  and  2069  and  Nelson  8786).  Furthermore,  many  plants  with  the  lax,  narrow  foli- 
age of  plattensis  have  all  of  the  bracts  tomentulose  as  in  frigidus  (for  example,  Goodding  588,  UC,  and  And£rson 
89  and  393,  UC).  Tlierefore,  the  only  satisfactory  treatment  is  to  include  in  typicus  plants  with  either  straight 
or  curved  leaves  and  vnth  bracts  varying  from  glabrous  to  puberulent.  The  type  of  the  species  is  discussed 
under  Chrysocoma  nau.'ieosa  of  this  list. 

36.  C.  FRIGIDUS  var.  concolor  Nelson,  Bot.  Gaz.  28:371,  1899. — C.  nauseosus  typicus  but  with  a  pale  yel- 
lowish-green herbage  and  somewhat  elongated  inflorescence.  The  leaves  are  straight,  flat,  and  ascending, 
the  bracts  of  the  involucre  mostly  puberulent  but  the  innermost  only  ciliate.  Type  locality,  Hutton  Lakes, 
Wyoming. 

37.  C.  GLAREOSUs  Rydberg,  Fl.  Rocky  Mts.  858, 1917. — Based  upon  Bigelovia  glareosa,  which  see. 

38.  C.  GNAPHALODES  Greene,  Pittonia  4:42,  1899. — C.  nauseosus  gnaphalodes. 

39.  C.  GRAVEOLENS  Greene,  Erythea  3: 108,  1895. — C.  nauseosus  graveolens. 

40.  C.  GRAVEOLENS  GLABRATA  Nelson,  in  Coulter  and  Nelson,  Man.  Rocky  Mts.  496:1909. — Based  upon 
Bigelovia  graveolens  glabrata,  which  see. 

41.  C.  JUNCEUS  Greene,  Erythea  3:113,  1895. — C.  nauseosus  junceus. 

42.  C.  LAETEVIRENS  Greene,  Pittonia  5:61,  1902. — A  light  green  form  or  state  of  C.  nauseosus  graveolens 
gathered  at  Grand  Junction,  Colorado. 

43.  C.  LATisQUAMEUs  Grecnc,  1.  c,  4:42,  1899. — C.  nauseosus  latisguameus. 

44.  C.  LEiosPERMUS  Greene,  Erythea  3:113,  1895. — C.  nauseosus  leiospermus. 

45.  C.  MACOUNi  Greene,  Pittonia  5 :  63,  1902. — Best  referred  to  C.  nauseosus  albicaidis,  although  the  corolla- 
tube  is  not  arachnoid  and  the  habit  suggests  that  of  the  plattensis  form  of  subspecies  typicus,  as  noted  by  Greene. 
But  the  corollas  are  8.5  to  9  mm.  long,  therefore  longer  than  in  typicus,  and  the  involucre  also  is  longer  (8.5  to 
9  mm.).  The  type  specimen  gives  no  indication  that  the  plants  are  low  in  stature.  Type,  Lytton,  British 
Columbia,  August  30,  1887,  Macoun  (Herb.  Greene). 

46.  C.  MOHAVENSis  Greene,  Erythea  3:113,  1895. — C.  nauseosus  mohavensis. 

47.  C.  MOQUiANUs  Greene,  Pittonia  5:60,  1902. — C.  nauseosus  bigelovi.  Greene  says  "achenes  not  seen," 
but  the  specimen  marked  as  the  type  in  his  herbarium  has  well-formed  achenes  and  these  axe  glabrous,  as  in 


C.    NAUSEOSUS.  221 

bigelovi.     The  habit  and  also  the  details  of  involucre  and  flowers  are  exactly  as  in  the  usual  form  of  this  sub- 
species.    Type  locality,  Moqui  Indian  Reservation,  northern  Arizona. 

48.  C.  NAUSEOSUS  (Pallas)  Britton,  in  Britton  and  Brown,  111.  Fl.  3:326,  1898.— This  i«  the  proper  combi- 
nation and  authority  for  all  of  the  subspecies  here  assembled  under  C.  nauseosxis,  although  Britton  used  the  name 
in  a  more  restricted  sense.  His  first  cited  synonym  is  the  same  as  C.  nauseosus  typicim,  but  subspecies  graveolens 
is  included  among  the  other  sjTionyms  and  in  the  description. 

49.  C.  NAUSEOSUS  ALBiCAULis  Rydberg,  Mem.  N.  Y.  Bot.  Gard.  1:385,  1900. — C.  nameosus  subspecies 
albicaulis,  at  least  as  to  synonymy. 

50.  C.  NAUSEOSUS  vars.  bernardinus,  bigelovi,  ceruminosus,  consimilis,  glareosus,  gnaphalodes, 

GRAVEOLENS,    HOLOLEUCUS,   JUNCEUS,    LATISQUAMEUS,   LEIOSPERMUS,   MOHAVENSIS,    OCCIDBNTALIS,    PINIFOLIUS, 

salicifolius,  speciosus,  and  viridulus,  all  Hall,  Univ.  Calif.  Publ.  Bot.  7:160  to  180,  1919,  are  here  trans- 
ferred to  subspecies  of  C.  nauseosus  without  change  of  name. 

51.  C.  NAUSEOSUS  bernardinus,  but  the  twigs,  leaves,  and  involucres  white  with  a  floccose  tomentum. 
Above  the  Mill  Creek  Falls,  San  Bernardino  Mountains,  California,  Parish  IISS  (DS).  Probably  grows  also 
on  San  Jacinto  Mountain,  as  indicated  by  an  incomplete  specimen  from  the  lower  edge  of  the  pine  belt  on  the 
north  side  (Hall  10701).  Apparently  bears  the  same  relation  to  bernardinus  that  albicaulis  does  to  speciosus 
but  the  form  is  too  little  knowTi  to  permit  of  final  taxonomic  treatment  at  this  time.  According  to  Parish, 
the  white  form  is  not  rare  in  the  San  Bernardino  Mountains,  where  it  grows  with  the  gray  or  greenish  form. 

52.  C.  NAUSEOSUS  var.  californicus  Hall,  1.  c,  174,  1919. — As  to  synonymy,  this  is  the  same  as  C.  calv- 
fornicus  of  the  present  list,  and  therefore  a  form  of  C.  nauseosus  albicaulis.  However,  the  description  and 
specimen  cited  belong  to  C.  parnji  bolaiideri. 

53.  C.  NAUSEOSUS  var.  frigidus  Hall,  1.  c,  170,  1919. — Based  upon  C.  frigidus  Greene,  which  see. 

54.  C.  NAUSEOSUS  var.  graveolens  Piper,  Contr.  U.  S.  Nat.  Herb.  11:559,  1906. — Based  upon  Chrysocoma 
graveokns  Nuttall,  here  transferred  to  Chrysothamnus  nauseosus  subspecies  graveolms. 

55.  C.  NAUSEOSUS  var.  oreophilus  Hall,  1.  c,  175,  1919. — Based  on  C.  oreophilus  Nelson,  which  see. 

56.  C.  NAUSEOSUS  var.  plattensis  Hall,  1.  c,  170,  1919. — Based  on  C.  speciosus  plattensis  Greene,  which  see. 

57.  C.  NAUSEOSUS  SPECIOSUS,  but  the  dense  gray  tomentum  extending  even  to  the  inner  bracts  of  the  invo- 
lucre; the  variation  not  named.  (Plate  33,  fig.  1.)  Waitsburg,  southeastern  Washington,  Horner  413  (UC); 
near  Clear  Creek,  Butte  County,  California,  Brown  46  (DS,  UC).  These  are  very  much  like  the  type  of  speci- 
osus, except  that  in  this  the  tomentum  stops  abruptly  with  the  lower  bracts  of  the  involucre.  Specimens  referable 
to  this  variation,  but  with  the  involucre  less  densely  tomentose,  are:  Leiberg  906,  910,  924,  and  946,  all  from 
eastern  Oregon.  Still  less  pubescent,  the  inner  bracts  nearly  glabrous,  is  a  plant  from  Ogden,  Utah  {Slilwell,  UC). 
The  heavily  tomentose  specimens  have  been  sometimes  identified  as  gnaphalodes,  but  differ  in  the  very  acute 
bracts  and  longer  coroUa-lobes  and  style-appendages. 

58.  C.  NAUSEOSUS  SPECIOSUS,  but  a  form  with  heavy  leaves  2  to  3  mm.  wide  and  close  rounded  cymes;  the 
form  not  named,  except  as  included  in  the  original  C.  californicus  Greene.  This  is  a  common  type  in  eastern 
and  northern  California,  and  western  Nevada,  and  is  very  strikingly  different  in  its  full  development.  It  is 
represented  by  the  collections  so  indicated  in  the  citations  under  subspecies  speciosus.  The  abundance  of  this 
form  toward  the  south  indicates  that  it  may  be  a  geographic  ecad  or  race.  Intermediates  are  plentiful  in  the 
intervening  territory  (Butler  1824;  Heller  12946),  and  also  to  the  eastward  (Utah,  Jones  503;  Wyoming,  Bran- 
degee).  It  is  probable  that  some  collections  of  this  variation  were  included  in  Greene's  conception  of  his  C. 
calif  amicus  (No.  25  of  this  list). 

59.  C.  NAUSEOSUS  VIRIDULUS. — A  dwarf  form  of  the  alkali  flats  of  Antelope  Valley,  southern  Cahfbrnia,  is 
referred  here  provisionally.  It  has  flexuous  stems,  short  rounded  inflorescences,  and  exceptionally  small 
flowers  (commonly  6  or  7  in  a  head),  but  the  flowers,  although  reduced  in  size,  have  the  narrow,  elongated,  and 
spreading  lobes  of  viridulus.  Representative  collections  are  Hall  10582  and  10587,  both  from  near  Lancaster. 
More  nearly  typical  specimens  have  been  gathered  in  the  San  Antonio  Mountains  at  an  altitude  of  2,440  m. 
(Johnston  1706). 

60.  C.  occidentalis  Greene,  Fl.  Francisc.  369,  1897. — C.  nauseosus  occidentalis. 

61.  C.  OREOPHILUS  Nelson,  Bot.  Gaz.  28:375,  1899. — A  low  form  of  C.  rmuseosris  consimilis  with  erect  and 
slightly  wider  upper  leaves.  Perhaps  intermediate  to  subspejies'jrareo^ens.  The  type  is  Nelson  4105  from 
Evanston,  Wyoming.     Other  specimens  distributed  under  this  name  are  mostly  subspecies  speciosus  and  typicus. 

62.  C.  OREOPHILUS  ARTUS  Nelson,  1.  c,  54:413,  1912. — Not  distinguishable  from  C.  nauseosus  consimilis. 
Type  locality,  Boise,  Idaho. 

63.  C.  ORTHOPHYLLUs  Greene,  Pittonia  5 :  62,  1902.— C.  nauseosus  albicaulis,  but  with  the  lobes  of  the  corolla 
sparsely  villous.  The  value  of  this  character  has  been  already  discussed  (p.  167).  Type  locality,  Big 
Meadows,  Plumas  County,  California. 

64.  C.  PALLiDUs  Nelson,  Bot.  Gaz.  28 :  372,  1899. — C.  nauseosus  typicus,  but  the  herbage  nearly  white  with 
a  very  smooth,  close,  persistent  tomentum  and  the  short  leaves  crowded  near  the  top.  The  type  is  from  alka- 
line flats  near  Laramie,  Wyoming,  and  the  form  occurs  elsewhere  in  alkaline  soil  of  Wyoming  and  northern 
Colorado. 


222  GENUS   CHKYSOTHAMNUS. 

65.  C.  PATENS  Rydberg,  Bull.  Torr.  Club  31  :  652,  1904. — C.  nauseosus  pinifolim,  but  a  form  with  spreading 
and  more  or  less  falcate  leaves.     Type  locality,  Colorado. 

66.  C.  PiNiFOLius  Greene,  Pittonia  5:60,  1902. — ('.  nauseosus  pinifolius. 

67.  C.  PLATTENSis  Greene,  1.  c,  4:42,  1809. — Based  upon  C.  speciosus  platiensis,  which  see  in  this  list. 

68.  C.  P0LCHERRIMUS  Nelson,  Bot.  Gaz.  28:370,  1899. — A  variation  of  C.  nauseosws  speciosus  recognized  in 
the  field  by  its  usually  more  robust,  tree-like  habit,  largar  leaves,  larger  inflorescences,  and  more  nearly  glabrous 
involucre.  It  seems  that  as  speciosus  moved  eastward  it  developed  this  fine  form  in  favorable  situations,  while 
subsjjecies  typiciis  came  to  occupy  the  less  favorable  ones.  The  connection  between  pulcherrimus  and  speciosus 
is  found  at  so  many  places,  both  in  the  field  and  in  the  laboratory,  that  the  former  is  looked  upon  as  the  result 
of  ecologic  conditions  and  not  of  taxonomic  rank.  Its  characters  are  strongly  suggested  by  No.  58  of  this  list, 
which  is  also  a  robust  form  with  even  larger  leaves,  but  with  a  slightly  different  involucre.  The  type  of  pul- 
cherriynns  is  a  specimen  from  Woods  Landing,  Wyoming,  Nelson  3477  (R). 

69.  C.  PUi.CHERRiMus  var.  fasciculatus  a.  Nelson,  Bot.  Gaz.  28:371,  1899. — The  same  as  pulcherrimus  (see 
preceding  note),  but  with  numerous  short  branchlets  and  crowded  rigid  leaves  only  2  to  3  cm.  long.  The  types 
came  from  Boulder  Creek  and  Creston,  Wyoming. 

70.  C.  SALiciFOLius  Rydberg,  Bull.  Torr.  Club  37: 130,  1910. — C.  nauseosus  salicifolius. 

71.  C.  SPECIOSUS  Nuttall,  Trans.  Am.  Phil.  Soc.  II,  7:323,  1840. — C.  nauseosus  speciosus. 

72.  C.  SPECIOSUS  0.  ALBicAULis  Nuttall,  1.  c,  324,  1840. — C.  nauseosus  albicaulis. 

73.  C.  SPECIOSUS  var.  (?)  arizonicus  Greene,  Erythea  3:110,  1895. — C.  nauseosus  latisquameus.  Although 
described  by  Greene  on  tlie  same  page  as  latisquameus,  the  only  tangible  differences  there  given  are  the  longer 
leaves  and  rather  deeply  cleft  corolla  in  arizonicus.  Tlie  specimens  at  hand  exhibit  much  too  great  a  fluctuation 
in  the  length  of  the  leaves  to  permit  the  use  of  this  as  a  character,  and  the  corolla-lobes  are  always  short,  as 
is  indicated  by  the  measurements  given  in  table  23.  A  search  for  the  type  at  the  Greene  Herbarium  was 
unsuccessful,  but  a  specimen  at  the  University  of  California  (Santa  Rita  Mountains,  Arizona,  November,  1891 , 
Brandtgee),  doubtless  of  the  type  collection,  has  leaves  2  to  4  cm.  long  and  corolla-lobes  0.8  to  1  mm.  long. 
The  herbage  of  this,  and  in  fact  most  specimens,  is  very  white,  whereas  the  type  of  latisquameus  is  less  notably 
so.  It  is  believed,  however,  that  this  difference  is  too  slight  to  be  compared  with  that  between  other  pairs  of 
subspecies  (see  p.  170). 

74.  C.  SPECIOSUS  var.  gnaphalodes  Greene,  1.  c. — C.  nauseosus  gnaphalodes. 

75.  C.  SPECIOSUS  var.  (?)  latisquameus  Greene,  1.  c. — C.  nauseosus  IcUisquameus. 

76.  C.  SPECIOSUS  var.  (?)  plattensis  Greene,  1.  c,  111,  1895.— A  form  of  C.  nauseosus  typicus  discussed  under 
C.  frigidus,  No.  35  of  this  list.  No  type  was  indicated,  but  the  distribution  was  stated  as  alkaline  plains  of  the 
Platte  and  elsewhere  along  the  eastern  base  of  the  Rocky  Mountains.  No  specimens  collected  by  Greene 
prior  to  1895  have  been  found  in  herbaria. 

77.  C.  tortuosus  Greene,  Pittonia  5:63,  1902. — Described  from  very  immature  specimens  from  Plumas 
County  and  Mount  Shasta,  California.  Probably  referable  to  C.  nauseosus  consimilis,  because  of  the  green  and 
glabrous  involucre  of  the  only  head  on  the  type  specimens  (in  Herb.  Greene).  The  corolla-lobas  in  this  young 
condition  are  about  2  mm.  long,  the  bracts  rather  pungently  acute  (suggesting  subspecies  occidentalis) ,  the 
leaves  nearly  filiform  and  more  or  less  spreading,  and  the  twigs  tortuous. 

78.  C.  TURDiNATUs  Rydberg,  Fl.  Rocky  Mts.  859,  1917. — C.  nauseosus  turbinatus. 

79.  C.  viRENS  Greene,  Pittonia  5:61,  1902. — C.  nauseosus  graveolens.  The  type  specimens  (in  Herb. 
Greene)  are  perhaps  a  little  greener  than  in  the  usual  form,  but  although  a  search  was  made  at  the  type  locality 
(Canon  City,  Colorado)  and  in  surrounding  districts,  no  specimens  were  found  that  could  be  satisfactorily 
separated,  either  on  color  or  on  other  features.  The  involucre  is  7  to  8  mm.  high  in  the  type  and  the  whole 
head,  to  the  tips  of  the  styles,  12  to  15  mm.  The  flowers  thus  protrude  farther  than  usual,  but  this  is  an  exceed- 
ingly variable  character.  The  bracts,  described  as  of  more  or  less  triangular  outline  and  scarcely  acute,  are  as 
in  typical  graveolens. 

80.  LmosYRis  ALBiCAUus  Torrey  and  Gray,  Fl.  N.  Am.  2 :  234,  1842. — C.  nauseosus  albicaulis. 

81.  L.  BiGELOVi  Gray,  Pacif.  R.  R.  Rep.  4':  98,  1857. — C.  nauseosus  bigelovi. 

82.  L.  CERUMiNOSA  Durand  and  Hilgard,  Jour.  Acad.  Nat.  Sci.  Phila.  II,  3 :  40,  1855.— C.  nauseosits  ceru- 
minosus. 

83.  L.  GRAVEOLENS  GLABRATA  Engelmann,  in  Gray,  Proc.  Am.  Acad.  8 :  645,  1873.— A  form  of  C.  nauseos-us 
graveolens,  judging  from  the  description.  Dr.  B.  L.  Robinson  writes  that  there  is  a  specimen  in  the  Gray 
Herbarium  collected  in  Nebraska  by  Henry  Engelmann  in  1856  and  labeled  "L.  graveolens,  glabrala,  H.  Engel- 
mann, 1860  (G.  Engelm.  in  litt.)  "  but  that  no  reference  to  the  name  can  be  found  in  any  of  Engelmann's  papers. 
It  seems,  therefore,  that  the  combination  was  published  only  in  Gray's  paper  as  cited. 


C.    NAUSEOSUS. 


223 


{/7.ce/-um/'nos{/s\  \o.  mo/>3i/e/7s/'s\ 


;gh,  sharply 
angled 


Style-appendages 
shorter  than  stig- 
matic  portion;  cor 
lobe  under  imm. 


Fia.  28.— Phylogenetic  chart  of  the  subspecies  of  Chrysothamnut  nouteosu* 


224  GENUS    CHRYSOTHAMNUS. 

RELATIONSHIPS. 

Chrysothamnus  nauseosus  is  very  distinct  from  all  other  species  except  C.  parryi,  but 
with  this  it  has  much  in  common.  Indeed,  reduced  forms  of  the  two,  in  which  the  type 
of  inflorescence  is  difficult  to  make  out,  are  sometimes  mistaken  for  each  other.  These 
occur  most  frequently  in  the  poor  soils  of  western  Wyoming  and  western  Colorado. 
Often  such  forms  can  be  placed  with  certainty  only  by  giving  close  attention  to  neighbor- 
ing plants  in  which  the  inflorescence  may  be  better  developed,  and  to  any  tendency 
toward  elongated  herbaceous  tips  of  the  involucral  bracts,  this  latter  a  mark  of  C.  parryi. 
A  minor  character,  possibly  indicative  of  the  common  origin  of  the  two,  is  the  growth  of 
long  weak  hairs  on  the  tips  of  the  corolla-lobes  in  certain  forms.  This  is  so  unusual  in 
the  Compositse  that  its  appearance  in  C.  parryi  latior  and  C.  pyramidatus,  and  also  in 
two  subspecies  of  C.  nauseosus  (junceus  and  turbinatus)  seems  to  have  more  than  ordinary 
significance. 

Variation  within  the  aggregate  here  taken  as  C.  nauseosus  has  been  so  marked  that 
numerous  striking  forms  have  resulted.  The  difficulty  in  according  specific  rank  to  these 
has  been  indicated  in  the  paragraph  introductory  to  the  key  to  the  subspecies.  The 
problem  of  organizing  them  into  natural  groups  is  a  very  complicated  one  because  of 
the  large  number  of  characters  involved  and  the  exceptionally  numerous  combinations 
of  these  as  represented  in  the  copious  collections  already  made.  Furthermore,  it  is 
often  impossible,  in  the  absence  of  a  detailed  genetic  analysis,  to  determine  whether 
certain  forms  are  merely  ecologic  variations  or  whether  they  are  based  upon  inheritable 
factors.  However,  much  time  has  been  given  to  detailed  fieM  studies,  to  transplant 
experiments,  and  to  a  close  analysis  of  herbarium  material.  The  results  of  these  studies 
are  graphically  set  forth  in  the  accompanying  diagram.  The  statistical  basis  for  some  of 
the  conclusions  is  given  in  table  23,  page  223.  According  to  the  arrangement  presented  in 
the  diagram,  the  species  comprises  two  major  assemblages  of  forms,  three  smaller  groups 
representing  lines  of  divergence  which  early  separated  from  the  parent  stock,  and  three 
small  assemblages  which  are  believed  to  be  marked  developments  from  one  or  the  other 
of  the  two  principal  groups.  Each  of  the  units  indicated  in  the  diagram  by  an  ultimate 
circle  is  composed  of  one  or  more  subspecies.  Each  subspecies,  in  turn,  is  usually  com- 
posed of  a  number  of  still  smaller  units — strains,  biotypes,  ecads,  etc. — which  are  not  given 
taxonomic  status,  but  the  more  noteworthy  of  which  are  discussed  as  minor  variations. 

All  of  the  subspecies  of  Chrysothamnus  nauseosus  are  so  highly  specialized  that  it  is 
difficult  to  select  any  one  as  the  most  primitive.  However,  in  some  cases  primitive  traits 
have  persisted  in  lines  which  exhibit  a  marked  development  in  other  features.  Thus, 
conspicuously  pilose  corolla-lobes,  found  also  in  C.  pyramidatus  and  in  forms  of  C.  parryi, 
here  occur  in  subspecies  junceus  and  turbinatus,  occasionally  also  in  albicaulis  and  bige- 
lovi.  With  these  and  similar  considerations  as  a  clue,  and  recalling  the  close  connection 
between  turbinatus  and  bigelovi,  the  opinion  is  ventured  that  the  first,  third,  and  fourth 
primary  diverging  lines  in  the  chart  represent  a  past  connection  through  primitive 
forms  now  extinct.  The  second  or  graveolens  line  is  in  more  doubt,  since  this  may  have 
arisen  directly  from  speciosus.  Therefore,  it  should  be  understood  that  the  placing 
of  turbinatus  and  its  allies  at  the  end  of  the  taxonomic  sequence  does  not  indicate  that 
these  are  more  highly  developed  than  the  others. 

The  two  larger  groups  of  the  subspecies  of  C.  nauseosus  may  be  referred  to  as  the 
typicus  branch  and  the  graveolens  branch  respectively.  They  differ  from  each  other  in  a 
number  of  involucral  and  floral  characters,  so  that  after  long  acquaintance  with  the  mem- 
bers one  comes  to  have  a  fixed  belief  in  the  reality  of  the  groups  as  natural  units  and  is 
able  unhesitatingly  to  place  a  majority  of  the  specimens  he  encounters  in  either  one  or 
the  other  of  the  two  assemblages.  These  characters,  however,  are  so  fluctuating  and 
overlapping  in  some  of  the  forms  that  they  can  not  be  used  in  keys,  so  for  this  purpose 


C.   NAUSEOSUS.  225 

it  is  better  to  fall  back  upon  a  distinction  based  upon  the  pubescence  of  the  involucre. 
This  character  runs  approximately  parallel  with  what  are  believed  to  be  natural  lines 
and  its  use  is  thus  very  convenient,  although,  as  is  to  be  expected  in  a  highly  variable 
species  like  C.  nauseosus,  some  forms  plainly  belonging  by  all  other  criteria  to  one  group 
of  subspecies  will  have  a  pubescence  of  the  involucre  which  very  closely  approaches  that 
of  the  other  group.  In  fact,  if  this  criterion  alone  is  used,  it  will  sometimes  lead  to  an 
erroneous  placing  of  a  subspecies,  especially  if  the  pubescence  is  very  scant  or  minute. 
Naturally,  the  pubescence  of  the  involucre  in  the  typicus  group  is  only  an  expression  of 
the  general  tendency  toward  an  excess  of  pubescence  in  the  whole  plant.  The  herbage  of 
all  of  the  members  of  this  group,  with  only  now  and  then  an  exceptional  form,  is  quite 
gray  or  sometimes  even  white  as  compared  with  the  usually  green  or  yellowish-green 
herbage  of  the  graveolens  branch.  The  two  can  not  be  accepted  as  distinct  species,  as  is 
evidenced  by  the  very  nature  of  the  character  used  for  their  detection  and  also  by  the 
frequent  intergrading  forms  just  mentioned.  The  contact  seems  to  be  between  speciosus 
and  graveolens,  since  forms  are  constantly  recurring  which  can  be  about  as  satisfactorily 
placed  in  one  as  in  the  other  of  these  subspecies.  It  seems  probable  that  speciosus  and 
graveolens  come  the  nearest  to  representing  the  ancestral  form  in  which  the  primary 
cleavage  took  place.  This  hypothesis  finds  some  substantiation  in  the  facts  of  geo- 
graphic distribution.  The  subspecies  speciosus  is  most  abundant  across  the  northerly 
part  of  the  Great  Basin,  that  is,  west  of  the  Rocky  Mountains,  while  graveolens  belongs 
chiefly  to  the  plains  and  valleys  of  the  Rocky  Mountain  States,  but  extends  northwest 
to  southern  Idaho,  thus  overlapping  the  range  of  the  former.  Ecologically,  speciosus 
belongs  to  mildly  alkaline  soil  and  runs  up  on  slopes  where  there  is  perhaps  no  alkali. 
The  other  members  of  the  typicus  group  are  inhabitants  of  non-alkaline  soils,  except  for 
occasional  forms  (especially  plattensis)  which  have  become  adapted  to  moderately  saline 
cqnditions.  On  the  other  hand,  graveolens  grows  in  soil  quite  strongly  alkaline  and 
among  the  other  subspecies  of  its  group  are  some  which  run  down  into  strongly  impreg- 
nated soils. 

In  following  the  typicus  branch,  it  is  first  noted  that  two  of  the  subspecies,  gnaphalodes 
and  hololeucus,  differ  so  radically  from  the  others  that  they  are  assigned  to  a  group  extra- 
neous to  the  principal  assemblage.  They  are  very  much  like  the  others  in  superficial 
appearance,  but  differ  from  all  of  them  in  the  very  short,  erect  teeth  to  the  corolla  and 
especially  in  the  comparatively  short  stylar  appendages,  although  both  of  these  struc- 
tures are  much  shortened  in  occasional  plants  of  other  subspecies.  By  reference  to  table 
23  it  will  be  seen  that  in  the  30  specimens  examined  the  appendage  is  always  shorter 
than  the  stigmatic  portion,  whereas  in  the  138  specimens  of  other  subspecies  the  append- 
age is  always  longer  than  the  stigma,  except  in  a  very  few  cases  (see  especially  sub- 
species typicus).  The  measurements  were  made  on  specimens  which  had  been  previously 
determined  as  gnaphalodes  and  hololeucus  because  of  their  other  characters.  The  short 
corolla-lobes  furnish  a  useful  criterion  for  the  identification  of  these  subspecies,  but  it  is 
not  always  strictly  applicable,  for,  as  will  be  seen  by  reference  to  the  table,  the  shortest 
lobes  in  others  are  not  infrequently  shorter  than  the  longest  ones  in  these.  But  the 
general  parallelism  between  these  two  characters,  together  with  the  peculiarly  aromatic 
odor  of  the  herbage,  and  certain  other  considerations,  leads  to  the  conclusion  that  the 
two  subspecies  under  consideration  are  closely  related  to  each  other  and  that  they  con- 
stitute an  evolutionary  group  quite  distinct  from  the  others.  Subspecies  gnaphalodes  is 
abundant  on  well-drained  soils  from  middle  Nevada  and  western  Arizona  to  the  Sierra 
Nevada,  while  hololeucus  occurs  only  as  scattered  individuals  or  in  small  groups  within 
this  same  area.  The  plants  of  the  latter  are  so  white  as  compared  with  the  former  that 
the  two  can  be  distinguished  in  the  field  without  difficulty.  The  origin  of  hololeucus  by 
mutation  at  different  places  and  times  seems  quite  probable. 


226  GENUS   CHRYSOTHAMNUS. 

Within  the  typicus  group  it  is  found  that  subspecies  speciostis  probably  includes  the 
plexus  from  which  the  others  have  arisen.  As  originally  described,  this  is  a  rather  low, 
narrow-leaved,  gray  plant  with  close,  rounded  inflorescences.  This  form  is  common  in 
the  basin  of  the  Columbia  River,  extending  south  through  eastern  Oregon  and  east  into 
Idaho,  etc.  Farther  southward  and  southeastward  it  passes  gradually  into  a  more  robust 
form  with  wider  leaves  (minor  variation  58),  while  to  the  east  it  becomes  taller,  but  with 
only  a  slight  widening  of  the  leaves.  In  the  Rocky  Mountain  States  it  is  commonly  a 
tall,  tree-like  shrub  with  large,  open  inflorescences,  the  involucres  more  nearly  glabrous, 
and  the  leaves  slightly  wider  than  in  the  typical  form.  This  most  easterly  variation 
has  been  described  as  C.  ■pulcherrimus  Nelson  (minor  variation  68).  It  comes  very  close 
to  connecting  spedosus  directly  with  graveolens.  Thus,speciosus  as  here  conceived  includes 
a  number  of  minor  variations,  which  can  be  correlated  roughly  with  geographic  distribu- 
tion, but  none  of  which  are  sufficiently  well  marked  to  be  given  definite  taxonomic  status. 
In  addition  to  these  there  are  five  stronger  groups,  each  of  which  is  given  subspecific  rank. 

The  subspecies  latisquameus,  a  tall  shrub  of  Arizona  and  New  Mexico,  is  perhaps  more 
distinct  from  spedosus  than  any  of  the  others  just  mentioned.  It  is,  however,  given  a 
position  close  to  spedosus,  because  of  its  possible  connection  with  a  preceding  subspecies, 
namely,  hololeucus.  In  common  with  this  latter  it  has  a  loose,  white  tomentum,  excep- 
tionally obtuse  involucral  bracts,  short  corolla-lobes,  and  a  tendency  toward  an  arach- 
noid pubescence  on  the  corolla-tube  (see  minor  variation  8).  However,  because  of  the 
proportionately  longer  style-appendages,  it  is  provisionally  referred  to  the  spedosus  group. 

The  subspecies  albicaulis  is  perhaps  the  least  distinct  from  spedosus  of  any  included 
in  this  circle,  having  only  its  floccose  and  very  white  tomentum  as  a  constant  character. 
However,  this  difference  holds  without  exception,  there  being  no  intermediates,  even 
when  the  two  grow  side  by  side.  The  nature  of  this  character  difference  has  been  dis- 
cussed on  page  170.  Typical  albicaulis  grows  with  typical  spedosus  in  the  Columbia 
River  Basin,  while  to  the  south  it  becomes  more  robust  and  the  leaves  are  wider  (minor 
variation  25),  thus  paralleling  a  similar  variation  found  in  southern  plants  of  spedosus. 
This  subspecies  extends  east  only  to  western  Montana  and  Utah.  It  is  looked  upon  as  a 
probable  mutation  from  the  western  form  of  spedosus. 

The  subspecies  typicus  is  now  definitely  restricted  to  certain  low  shrubs  of  the  plateaus 
of  the  northern  Rocky  Mountain  States.  It  has  been  frequently  assumed  that  typical 
C.  nauseosus  was  the  northwestern  plant  here  called  subspecies  albicaulis.  The  error  of 
this  application  of  the  name  is  discussed  under  minor  variation  20,  where  the  identity  of 
the  original  Chrysocoma  nauseosa  with  the  plant  often  known  as  Chrysoihamnus  frigidu^ 
is  pointed  out.  Subspecies  typicus  is  looked  upon  as  an  easterly  derivative  of  spedosits 
which  has  undergone  a  reduction  in  the  size  of  the  heads  and  flowers  and  which  has 
assumed  certain  vegetative  characters  that  enable  it  to  persist  under  the  unfavorable 
conditions  of  its  cold,  bleak,  and  sometimes  alkaline  habitat.  Its  most  important  minor 
variations  probably  are  ecads,  since  they  are  recognizable  only  by  the  size  and  direction 
of  the  leaves  (minor  variation  35,  C.  frigidu^,  and  minor  variation  67,  C.  plattensis). 

The  subspecies  salidfolius  is  but  little  known,  but  seems  to  have  split  off  from  subspe- 
cies spedosus  along  the  southeastern  limits  of  the  range  of  this  latter.  It  is  a  robust  plant 
with  exceptionally  wide,  3-nerved  leaves. 

The  most  unique  feature  in  the  spedosus  group  has  been  developed  in  the  subspecies 
ocddentalis.  This  is  the  abrupt  narrowing  of  the  tips  to  the  involucral  bracts.  The 
narrowing  is  least  noticeable  in  plants  of  northern  California,  where  the  two  subspecies 
are  in  contact,  but  it  becomes  more  and  more  pronounced  toward  the  south.  The 
bracts  are  only  slightly  puberulent  or  sometimes  practically  glabrous  and  the  heads  are 
in  small,  compact,  globoid  cymes.  The  following  note  on  ocddentalis  is  from  a  recent 
paper  by  Hall  (Univ.  Calif.  Publ.  Bot.  7:168,  1919). 


C.    NAUSEOSUS.  227 

"The  distribution  of  this  variety  was  originally  stated  by  Greene  to  be  'In  the  Coast  Range,  from  Humboldt 
County  (California)  southward.'  Later,  this  same  author  stated  it  as  'Kern  and  Santa  Barbara  counties' 
(Fl.  Francisc.  369,  1897).  This  restriction  in  the  adopted  range  was  perhaps  due  to  the  fact  that  certain  speci- 
mens from  Humboldt  and  other  northern  counties  do  not  meet  the  requirements  of  the  description  as  well  as 
those  from  farther  south.  The  cuspidate  bracts  and  long  corolla-lobes,  together  with  the  habit  (especially  the 
small  compact  rounded  inflorescence),  are  here  taken  as  the  most  satisfactory  characters  for  the  variety.  Accept- 
ing this  definition,  we  find  fairly  typical  collections  from  the  dry  inner  north  Coast  Ranges  and  from  the  southern 
Sierra  Nevada  and  San  Bernardino  Mountains.  North  and  east  of  Trinity  County  it  apparently  passes  into 
speciosiis,  from  which  it  scarcely  differs  save  in  the  more  nearly  glabrous  and  abruptly  pointed  bracts.  At  its 
southernmost  stations  it  meets  and  perhaps  merges  into  bemardinus." 

A  specimen  in  the  Greene  Herbarium  collected  by  Miss  Eastwood,  September,  1894,  and 
marked  by  Greene  "C.  occidentaUs,  type!  in  Fl.  Fr.,"  may  be  considered  the  type.  This 
is  the  narrow-leaved  form  of  his  later  concept.  There  is  here  also  a  specimen  labeled 
as  "C.  californicus  var.  occidentaUs,  Eryth.  3:112"  (Siskiyou  Mountains,  September, 
1889,  Greene),  but  this  is  the  broad-leaved  plant  now  included  in  subspecies  speciosus 
(minor  variation  58).  Its  bracts  are  not  especially  acute,  while  abruptly  acute  bracts, 
united  with  narrow  leaves  and  small  compact  cymes  are  characteristic  of  subspecies 
occidentaUs  as  here  defined. 

Subspecies  bernardinus  is  so  distinct  from  the  other  members  of  the  typicus  branch  that 
it  is  placed  (in  the  diagram)  in  a  special  extruded  circle.  Because  of  the  essentially 
glabrous  involucre,  this  circle  has  also  a  tentative  connection  with  the  graveolens  group, 
although  it  is  extremely  doubtful  if  these  two  are  of  common  origin.  On  the  other  hand, 
bernardinus  resembles  certain  Rocky  Mountain  forms  of  speciosus  (once  distinguished  as 
pulcherrimus)  both  in  general  appearance  and  in  technical  characters,  but  the  involucre 
is  longer  and  the  more  strongly  keeled  bracts  are  acuminate  instead  of  merely  acute.  Its 
wide  geographic  separation  casts  considerable  doubt  on  the  theory  of  its  origin  from  such 
forms.  It  is  more  likely  a  descendant  from  speciosus  as  it  occurs  in  northern  California, 
the  modifications  being  associated  with  its  habitat  on  the  mountains  of  the  southern  part 
of  the  State,  and  it  is  not  at  all  impossible  that  the  connection  has  been  through 
occidentaUs. 

As  previously  indicated,  the  subspecies  graveolens  is  considered  as  the  beginning  of  the 
graveolens  branch,  all  of  the  members  of  which  are  inhabitants  of  alkaline  soil.  The 
steps  between  it  and  the  others  are  so  gradual  that  except  in  a  detailed  monograph  the 
whole  group  might  be  taken  as  constituting  a  single  subspecies.  The  original  graveolens 
is  a  plant  with  linear,  partly  3-nerved,  smooth  leaves,  as  described  by  Nuttall  and  as 
indicated  by  the  type  at  the  Academy  of  Natural  Sciences  of  Philadelphia.  The  leaves 
in  the  type  are  1.5  to  2  mm.  wide  and  the  cymes  4  cm.  across.  This  is  the  robust,  green 
form  with  large  rounded  inflorescences  that  is  so  common  in  the  easterly  part  of  the  range 
of  the  genus,  especially  in  Wyoming,  Colorado,  and  northern  New  Mexico.  It  presents 
many  minor  variations  as  to  size  and  direction  of  leaf,  height  of  involucre,  etc.  Similar 
variations  occur  in  the  other  member  of  the  group,  and  they  are  so  numerous  and  so  often 
intangible  that  their  recognition  as  taxonomic  units  is  not  feasible.  The  several  supposed 
species  (angustus,  confinis,  falcatus,  laetevirens,  oreophilus,  patens,  virens)  based  upon 
such  characters  are  included  in  the  list  of  minor  variations  (p.  218),  where  they  are  briefly 
discussed.  A  majority  of  these  have  been  studied  at  their  type  localities  and  in  the  her- 
baria where  the  type  specimens  are  deposited.  It  is  believed  that  most  if  not  all  of  them 
are  either  ecologic  or  seasonal  forms. 

The  three  subspecies,  pinifolius,  consimilis,  and  viridulus,  are  of  much  more  importance 
than  the  forms  just  mentioned.  This  is  because  they  represent  certain  well-defined 
and  fairly  consistent  tendencies,  especially  in  floral  structure,  and  also  because  each 
belongs  to  its  own  geographic  area.  There  are,  however,  frequent  intergradations  in 
all  of  the  characters,  especially  where  the  geographic  boundaries  meet,  so  that  some 


228  GENUS   CHRYSOTHAMNUS. 

specimens  can  not  be  definitely  assigned  to  a  particular  subspecies.  Subspecies  pinifoHus 
most  closely  resembles  graveolens,  but  has  much  narrower  1-nerved  leaves.  It  is  abundant 
on  alkaline  plains  of  the  southern  Rocky  Mountain  region.  From  western  Wyoming 
and  Colorado  to  Oregon  and  western  Nevada,  that  is,  almost  throughout  the  Great 
Basin,  the  commonest  subspecies  is  consimiHs.  This  is  a  more  slender  plant  than 
pinifoUus  and  the  corolla-lobes  are  1  to  2  mm.  long,  as  contrasted  with  0.5  to  1  mm. 
for  that  subspecies.  Perhaps  because  of  their  length,  the  corolla-lobes  are  inclined  to 
spread  or  recurve.  The  inflorescence  is  often  quite  elongated,  although  in  some  cases, 
especially  in  dwarfed  plants,  it  is  as  rounded  as  in  the  common  form  of  pinifoHus.  To 
the  southwest  of  the  consimiHs  area,  and  especially  in  the  alkaline  valleys  of  west  central 
Nevada  and  eastern  California,  is  found  the  more  robust  subspecies  viridulus,  a  form 
in  which  the  corolla-lobes  attain  the  length  of  2  to  2.5  mm.,  this  being  the  longest  in 
the  genus.  The  forms  and  relationships  of  this  were  discussed  by  its  author  as  follows 
(Hall,  Univ.  Calif.  Publ.  Bot.  7:178,  1919): 

"This  is  the  common  form  on  alkaline  flats  in  southern  Mono  County  and  in  Inyo  County,  California,  and  in 
western  Esmeralda  County,  Nevada,  although  there  are  many  slight  variations  from  the  type  as  described 
above.  Almost  every  valley  exhibits  forms  not  exactly  like  those  in  any  other.  The  variations  are  chiefly  in 
habit,  pubescence,  leafiness,  size  and  shape  of  inflorescence,  shape  of  bracts,  and  length  of  corolla-lobes.  The 
plants  range  in  height  from  a  few  dm.  to  nearly  3  m.,  but  are  always  taller  than  broad  unless  abnormal;  the 
corollas  vary  from  8  to  10  mm.  in  total  length;  the  corolla-lobes  are  seldom  shorter  than  2  mm.,  yet  in  two  col- 
lections there  are  some  flowers  with  lobes  only  1.7  mm.  long;  although  the  involucres  of  the  type  are  only  6  to 
7  mm.  long,  they  vary  in  other  specimens  to  8  or  even  9  mm. ;  the  mature  pappus  is  7  to  9  mm.  long.  *  *  * 
As  to  relationships,  viridulus  probably  is  a  southwestern  derivative  of  consimiHs  (or  vice  versa),  from  which  it 
differs  in  the  larger  corollas  with  longer  lobes,  the  thicker,  more  robust,  and  rigid  twigs  and  leaves,  the  heavier 
and  more  rounded  inflorescence,  and  the  stronger  odor  of  the  herbage.  These  characters  are  far  from  constant 
at  aD  stations.  The  length  of  the  corolla-lobe  is  the  most  satisfactory.  Of  twenty-seven  collections  taken 
throughout  the  established  range  of  the  variety,  only  five  have  corolla-lobes  2  mm.  or  less  long;  of  twenty-two 
collections  from  the  range  of  consimiHs  none  exhibit  corolla-lobes  of  over  2  mm.  in  length;  where  the  ranges 
meet,  as  around  Mono  Lake  and  at  Sodaville,  Nevada,  intermediate  sizes  are  frequent  and  here  the  other  differ- 
entiating characters  also  intergrade." 

It  should  not  be  inferred  from  the  above  that  these  varieties  actually  intergrade, 
because  some  of  their  characters  do  so.  What  appear  to  be  intergrades  may  in  reality 
be  hybrids.  On  the  other  hand,  the  phylogenetic  line  from  graveolens  through  pinifoHus 
and  consimiHs  to  viridulus  seems  reasonably  well  established. 

Two  subspecies,  both  derivatives  of  viridulus,  are  indicated  as  lying  outside  of  the 
graveolens  circle,  because  of  the  marked  development  of  certain  features.  In  ceruminosus 
the  tips  of  the  involucral  bracts  are  abruptly  narrowed  and  recurved.  No  intermediate 
stages  are  known,  but  the  form  has  been  collected  only  twice.  The  subspecies  mohavensis 
is  a  southern  and  far  western  derivative  of  viridulus  and  belongs  to  higher,  less  alkaline 
slopes.  It  is  distinguished  by  an  exceptionally  long  involucre,  the  sharply  keeled  bracts 
of  which  fall  into  very  well  defined  vertical  rows.  It  was  first  described  as  sparsely 
leafy  or  leafless,  but  there  is  a  tendency  throughout  the  graveolens  group  toward  an  early 
dropping  of  the  leaves.  Intermediates  are  sometimes  found  in  which  the  habit  is  that 
of  ynohavensis,  except  for  the  more  persistent  leaves,  the  bracts  are  in  sharply  defined 
vertical  rows,  but  acute  as  in  viridulus,  and  the  involucre  and  corolla-lobes  are  exactly 
intermediate  in  length  (Oak  Creek,  westerly  side  of  Owens  Valley,  California,  Hall 
10611). 

In  taking  up  the  third  main  line,  it  is  found  to  lead  to  a  group  of  only  two  subspecies, 
namely,  junceus  and  turhinalus.  These  are  almost  unique  in  the  species  in  that  their 
corolla-lobes  are  externally  villous  with  long  delicate  hairs.  This  character  reappears, 
however,  in  a  form  of  subspecies  albicaulis  (see  minor  variation  63),  in  one  subspecies 
of  C.  howardi,  and  in  C.  pyramidatus.     Subspecies  junceus  is  a  nearly  leafless,  little- 


C.   NAUSEOSUS.  229 

known  shrub  of  eastern  Arizona.  It  is  usually  described  as  cinereous,  or  minutely 
canescent,  but  the  twigs,  even  in  the  type,  have  the  usual  pannose  tomentum.  Sub- 
species turbinatus,  also  a  rare  plant,  known  only  from  Utah,  is  more  striking  because 
of  its  elongated,  cylindric  involucres,  but  no  character  can  be  found  as  a  basis  for  a 
distinct  species.  The  original  description  reads  "plants  glabrous  and  a  little  glutinous 
even  to  the  flowers."  The  type  collection  and  two  others  have  been  examined.  In  all 
of  these  the  copious  tomentum  of  the  twigs  is  so  closely  packed  that  it  gives  the  appear- 
ance of  a  glabrous  surface,  the  leaves  are  tomentulose,  and  the  corolla-lobes  hairy. 
Junceus  and  turbinatus  are  similar  not  only  in  the  points  mentioned,  but  also  in  habit 
and  distribution.  They  appear  to  form  an  offshoot  which  sprang  from  the  main  stock 
at  an  early  stage  in  the  development  of  the  genus.  Their  close  connection  with  sub- 
species glareosus  and  hiospermus  is  evidenced  by  the  variable  nature  of  the  pubescence 
on  the  corolla-lobes,  by  the  erratic  occurrence  of  this  in  bigeJovi  (see  p.  167),  and  by  transi- 
tions between  glabrous  and  pubescent  achenes,  as  will  be  indicated  under  leiospermus. 

The  last  group  to  be  considered  is  the  one  with  glabrous  achenes.  The  three  sub- 
species that  comprise  it  all  come  from  the  arid  southerly  portion  of  the  Great  Basin 
and  are  sufficiently  alike  in  essential  characters  to  lead  to  the  conclusion  that  the  group 
is  probably  a  natural  one.  The  absence  of  pubescence  on  the  achenes  is  not  of  specific 
taxonomic  significance,  as  is  indicated  by  collections  of  leiospermus  made  near  Caliente, 
Nevada  {Hall  10791,  10795).  In  some  of  these  plants  the  achenes  are  very  sparsely 
pubescent  on  the  edges,  in  others  they  are  sparsely  pubescent  both  along  the  nerves 
and  on  the  intervening  spaces.  At  this  station  the  conditions  are  extremely  xerophytic. 
This  is  reflected  in  the  plants,  which  are  quite  leafless,  thus  resembling  those  of  junceus 
in  appearance.  There  is  considerable  variation  in  the  color  of  the  tomentum  in  leio- 
spermus. The  first  specimen  cited  under  the  original  description  has  twigs  that  are  white 
in  the  inflorescence  and  for  a  distance  of  about  1  dm.  below  the  heads,  while  from  there 
down  they  are  yellowish-green;  in  the  other  specimen  cited  the  twigs  are  very  white 
down  to  the  old  wood;  in  more  recent  collections,  such  as  those  from  Caliente,  Nevada, 
the  twigs  are  green  throughout.  The  subspecies  glareosus  and  bigelovi  differ  from 
leiospermus  not  only  in  their  pubescent  involucres,  but  in  matters  of  habit,  in  the  more 
definite  ranks  of  the  bracts,  and  in  the  greater  length  of  the  involucre.  All  of  these  last 
five  subspecies  inhabit  the  southern  part  of  the  Great  Basin.  They  have  been  greatly 
modified,  especially  in  habit  and  foliage  characters,  and  these  modifications  enable  them 
better  to  cope  with  their  very  arid  and  often  alkaline  habitat. 

ECOLOGY. 

In  general,  the  important  subspecies  of  Chrysothamnus  nauseosus  are  subclimax 
dominants  of  the  sagebrush  association.  Forms  of  graveolens  are  abundant  in  the  western 
portions  of  the  mixed  prairie,  and  of  speciosus  in  particular  in  the  bunch-grass  prairie 
of  the  Northwest.  They  extend  northward  into  Canada,  but  are  found  in  the  drier 
parts  of  the  Southwest  only  in  valleys  in  the  mountains.  As  a  rule,  they  mix  and  alter- 
nate with  the  sagebrush,  except  for  such  halophytes  as  consimilis  and  viridulus,  which 
often  form  pure  stands  on  alkali  flats  below  it,  in  association  with  Distichlis  and  Iva 
axillaris.  The  pinifolius  form  of  graveolens  is  also  frequently  halophytic,  when  it  grows 
in  mixture  with  Sarcobatus.  All  of  these  are  serai  dominants,  and  with  drainage  or 
shifting  climate  yield  to  the  subclimax  dominants,  such  as  speciosus,  gnaphalodes, 
hololeucus,  albicaulis,  etc.  Graveolens  is  characteristic  of  the  cliff  edges  and  gullies  of 
the  bad  lands  of  western  Nebraska  and  the  Dakotas. 

This  species  reproduces  readily  from  seed,  and  grows  vigorously  when  transplanted, 
even  when  the  crowns  are  divided.  It  forms  basal  sprouts  after  cutting,  but  only  rarely 
when  burned.  Most  of  its  forms  are  among  the  latest  bloomers  of  the  genus,  the  flowers 
appearing  in  September  and  often  continuing  into  December. 


230 


GENUS   CHRYSOTHAMNUS. 

Table  23. — Variation  in  certain  sxibspecies  of  Chrysothamnus  nauseosua.' 


Length 

includiDg 

lobes. 


Lobe- 
length. 


Ratio  of 

lobe-length 

to  total 

length. 


Stig- 
ma tic 
portion, 
length. 


Append- 
age, 
length. 


Ratio  of 
appendage- 
length  to 
total  length 
of  branch. 


Subspecies  a.  gnaphalodea: 

pyramid  Lake,  Nev 

Reno,  Nev 

Lyon  County,  Nev 

Candelaria,  Nev 

GoldBeld,  Nev 

Carson  Sink  Region,  Nev, 
Benton,    Mono    County, 

Calif 

Inyo  County,  Calif 

Bishop,  Calif 

Kearsarge,  Calif 

Rosamond,  Kern  County, 

Calif 

Lancaster,  Calif 

Do 

Near  Lancaster,  Calif 

Do 

Do 

Saugus,  Calif 

Barstow,  Calif 

Banning,  Calif 

Average 


87247  UC 
65323  UC 
203114  UC 
203124  UC 

203117  UC 
128633  UC 

203129  UC 

203118  UC 
203120  UC 

203119  UC 

87246  UC 

203111  UC 
203110  UC 

203112  UC 

203113  UC 
194547  UC 

87243  UC 
203116  UC 
134761  UC 


Subspecies  6.  hololeucus: 
Pyramid  Lake,  Nev. 


Esmeralda  County,  Nev. . 
Benton,    Mono    County, 

Calif 

Do 

Bishop  Creek,    Inyo 

County,  Calif 

Oak  Creek,  Inyo  County, 

Calif 

Do 

Independence,  Inyo 

County,  Calif 

Inyo  County,  Calif 

Average 


203104  UC 
203103  UC 
178984  UC 
203102  UC 


194534  UC 
31196  UC 


Subspecies  c.  tpeciosus: 

Woods  Landing,  Wyo' . . . 
Fremont  County,  Wyo.'. . 

Southeastern  Utah' 

Boise,  Idaho* 

Near  Salt  Lake,  Utah 

Do 

Near  Grantsville,  Utah'.  . 
Eastern  Oregon* 

Do' 

Siskiyou  Mountains,  Orcg. 
Ormsby  County,  Nev.'. .  . 
Glenbrook  Nev.' 

Do' 

Lake  Tahoe,  Calif.' 

Placer  County,  Calif.' 

Modoc  County,  Calif.'.  .  . 

Yreka,  Calif.' 

Mono  Lake,  Calif.' 

Lundy,     Mono     County, 

Calif.' 

Upper  San  Joaquin,  Calif.' 

Average 


10662  R 
51497  UC 
176844  UC 
168807  UC 

203197  UC 

203198  UC 
203196  UC 
175221  UC 
175223  UC 

CI 
75408  UC 
128752  UC 
129585  UC 
195527  UC 
194094  UC 
195526  UC 
165409  UC 
203095  UC 


9.0 
9.6 
8.0 
7.8 

10.5 
9.5 
9.5 
9.2 

10.0 
8.6 

10.0 

10.5 
9.0 
8.8 


10.0 
8.0 
9.0 
8.5 
10.0 
8.0 
8.0 
10.0 
9.0 
10.5 
11.0 
11.0 
9.5 
10.0 
10.0 
9.0 
9.5 


mm. 
0.7 
0.9 
0.7 
0.5 
0.8 
0.7 

0.6 
0.6 
0.5 
0.5 

0.8 
0.6 
0.6 
0.7 
0.8 
0.6 
0.6 
0.7 
0.8 


1.0 
1.0 
0.4 
1.5 


p.ct. 

8.2 
10.9 

8.8 

6.2 
10.0 

8.8 

7.7 
7.8 
6.4 
7.0 

10.6 
8.6 
6.2 
8.0 

11.2 
6.6 
7.5 
9.4 

10.0 


11.2 
11.2 
12.3 
7.6 


21.1 
10.0 
12.5 
6.0 
16.0 
14.4 
16.1 
15.4 
16.3 
16.7 
20.0 
14.0 
14.4 
14.7 
13.3 

17.3 


1.4 
1.3 

1.6 
1.6 
1.8 
1.0 
1.6 
2.0 
1.6 
1.5 
1.8 
1.8 
2.0 
1.6 
2.0 
1.4 
1.6 
1.5 


2.4 
2.0 
1.6 
1.8 
2.3 
2.0 
2.6 
2.3 
2.6 
2.8 
2.0 
2.6 
2.0 
2.2 
2.0 


p.ct. 
44.0 
42.3 
40.0 
43.4 
42.8 
41.6 

47.6 
45.4 
45.4 
43  4 

44.0 
46.4 
44.4 
41.6 
44.0 
48.1 
48.0 
46.1 
46.8 


46.8 
46.4 
48.0 
44.4 


67.6 
58.0 
60.5 
61.5 
52.6 
60.0 
64.5 
53.4 
57.1 
62.5 
56.0 
69.0 
58.3 
55.5 
55.5 


For  footnotes,  see  page  ! 


C.   NATJSEOStrS.  231 

Table  23. — Variation  in  certain  tubspecies  of  Chrysothamnus  nauseosus — Continued. 


Length, 

including 

lobes. 


Corolla. 


Lobe- 
length. 


Ratio  of 

lobe-length 

to  total 

length. 


Style. 


Ratio  of 
appendage- 
length  to 
total  length 
of  branch. 


Subspecies  d.  latisguameus: 
White  S.inds,  N.  Mex.  .  . 
Burro      Mountains,      N. 


Me 


San  Lorenzo,  N.  Mex.  .  . 
Eastern  New  Mexico. ... 
Mimbres  R.,  N.  Mex.  .  .  . 
Santa    Rita     Mountains, 

Ariz 

Santa  Cruz,  Sonora 

Average 

Subspecies  e.  alhicaulis: 

Tranquille,  B.  C 

Poison,  Mont 

Wawawai,  Wash 


125334  UC 

US 

498228  US 

Gr 

Gr 


Warm  Springs,  Oreg.  . 

Eastern  Oregon 

Plumas  County,  Calif.' 

Modoc  County,  Calif. 

Lassen  County,  Calif. 

Average 


NY 

NY 

Mo.    Hot. 

Card. 
381002  US 
179775  UC 
26296  Gr 
11662  CI 
11681  CI 


Subspecies  /.  lypieus: 

Missouri  River  (type) . 

Douglas,  Wyo.« 

Church  Buttes,  Wyo.». . 
Sheridan,  Wyo 

Do 

Howell  Lakes,  Wyo. . .  . 

Tipton,  Wyo 

Laramie,  Wyo.' 

Do 

Do 

Do 

Do 

Do 

Laramie  Plateau,  Wyo.' 
Albany  County,  Wyo.  . 

Do 

Do 


Do. 


Colorado- Wyoming  line". 

Windsor,  Colo.' 

Do« 

Fort  Collins,  Colo' 

Boulder,  Colo.' 

East  Denver,  Colo.' 

Aurora,  Colo.' 

Average 

Subspecies  h.  occidenlalit: 

Sierra  Nevada  Mountains, 
Calif 

San  Bernardino  Moun- 
tains, Calif 

Southern  Sierra  Nevada, 
Calif 

North  Coast  Ranges,Calif. 

Do 

Average 


PhUa. 
146485  UC 
205537  UC 
38382  R 
78175  R 
187661  UC 
CI 
CI 
29415  R 
15383  R 
193529  UC 
51773  UC 
5692  R 
CI 
29414  R 
52302  R 
42089  R 
37246  R 
29429  R 
31151  R 
9396  R 
CI 
57235  R 
CI 
CI 


195543  UC 
196665  UC 
69867  UC 


9.0 
9.7 
7.5 


7.5 
8.0 
6.7 
8.2 
8.0 
7.4 


6.5 

7.7 
8.1 
8.1 
8.0 
7.7 
7.0 
7.0 
7.1 


6.5 
7.5 


8.2 
10.0 
7.5 
8.2 


0.6 
0.7 
0.7 
0.6 

0.9 
0.9 
0.6 


10.0 
8.6 

8  0 
9.0 
9.0 
9.5 
10.0 


20.0 
14.4 
18.8 


7.2 
7.0 
7.9 
7.6 
8.2 
7.0 


7.0 
7.0 
7.9 
6.6 
7.8 


7.0 
6.5 
7.5 
7.0 
8.0 
6.2 
7.4 


19.4 
18.6 
16.4 
22.4 
25.6 
18.6 
21.4 
17.4 
20.3 
19.7 
17.1 
21.4 


18.3 
22.2 
20.0 
22.1 
25.1 
23.1 
16.0 
25.7 
21.2 
22.8 


10.5 
9.5 

9  0 

8.8 

9.6 


20.9 

24.2 

22.2 
23.9 
17^  0_ 
21 .6 


64.1 
67.1 
65.6 


54.3 
59.2 
60.0 
48.4 
51.3 
55.5 

40.0 
48.1 
50.0 
62.6 
54.6 
46.1 
61.8 
36.1 
67.8 
60.0 
51.6 
54.3 
66.7 
61.6 
60.5 
55.9 
51.6 
JOM_ 
54.0 


56.7 

57.1 
64.7 

67.9 


For  footnotes  see  page  ; 


GENUS   CHRYSOfHAMNUS. 
Table  23. — Variation  in  certain  subspecies  of  Chrysothamnus  nauseosus — Continued. 


Invo- 
lucre- 
length. 


Length, 

including 

lobes 


Lobe- 
length. 


Ratio  of 

lobe-length 

to  total 

length. 


Stig- 
ma tic 
portion, 
length. 


Append- 
age, 
length. 


Ratio  of 
appendage- 
length  to 
total  length 
of  branch. 


Subspecies  t.  bemardinus: 
San   Gabriel   Mountains, 

CaUf 

Do 

San     Bernardino    Moun- 
tains, Calif,  (type).. 

Do 

Do 

Do 

San  Jacinto    Mountains, 

Calif 

Do 

Average 

Subspecies  j.  graveolens: 

Platte  Cafion,  Wyo 

New  Windsor,  Colo 

North  Denver,  Colo 

Fremont  County,  Colo . . , 

Sierra  La  Sal,  Utah 

South    of     Fort   Collins, 

Colo 

Do 

Golden,  Colo 

North   of    Fort    Collins, 

Colo 

Do 

Golden,  Colo 

North  Denver,  Colo 

Gunnison,  Colo 

Farmington,  N.  Mex 

Salida,  Colo 

Average 


SF 
SF 

149208  UC 
69265  UC 

111298  UC 
64990  UC 


51495  UC 
34342  UC 

148163  UC 
87244  UC 

135110  UC 

CI 
CI 
CI 

CI 
CI 
CI 
CI 
8411  R 
685894  US 
Gr 


Subspecies  fc.  pinifoliua: 

Salida,  Colo 

San  Luis  Valley,  Colo. 


Do. 


Gunnison,  Colo 

Do 

Doyles,  Colo 

West  Central  Colorado .  .  . 

Do 

Ida,  Colo 

White  Mountains,  N.Mex. 

Above  Datil,  N.  Mex 

Gunnison,  Utah  (type).  . 

Do 

Average 


203157  UC 

203158  UC 
203156  UC 

55167  UC 
R 
R 

55168  UC 
161363  UC 
412299  US 

Gr 
112410  UC 
26307  Gr 
412455  US 


Subspecies  I.  consimilis: 

Boise,  Idaho 

Stockton,  Utah 

Maggie     Creek,    Elko 

County,  Nev 

Deeth,  Nev.  (type) 

Elko  County,  Nev 

Caliente,  Nev 

Fallon,  Nev 

Mountain  House,  Nev .  .  , 

Reno,  Nev 

Pyramid  Lake  Road,  Nev. 


65304  UC 
26603  Gr 
175163  UC 
203106  UC 
176430  UC 
203146  UC 
87227  UC 
203194  UC 


12.1 
11.2 

12.0 
11.0 
12.0 
10.0 


10.7 
10.2 

9.5 
9.0 
10.0 
10.0 


p.ct. 
20.6 
17.7 

20.0 
22.2 
18.0 
15.0 

20.8 
20.0 


8.7 
10.0 
8.7 
8.3 
15.0 

16.2 
16.2 
14.6 

14.4 
14.4 
16.2 
18.5 
15.2 
17.1 
13.3 


1.6 
1.8 
2.0 
2.0 
1.9 

2.0 
2.0 
1.8 

1.8 
2.0 
1.9 
2.1 


18.5 
17.4 
14.0 
9.5 
12.8 
13.3 
11.1 
10.0 
13.6 
14.4 


8.0 
7.9 
7.0 
8.0 
7.2 
8.5 
7.6 


17.1 
13.7 
22.2 
17.5 
17.1 
18.3 


65.2 
56.2 
57.1 


54.3 
52.6 
65.5 
58.1 
58.6 


58.3 
52.6 
56.5 
54.5 


57.1 
64.6 
56.3 
50.0 
56.6 
48.0 
50.0 


52.8 


67.1 
61.6 


51.6 
58.0 
66.6 
64.2 
50.0 
53.6 
56.0 


For  footnotes  see  page  233. 


C.    NAUSEOSUS. 
Table  23. — Variation  in  certain  svbspeeies  of  Chrysothamnus 


233 


Invo- 
lucre- 
length. 


Length, 

including 

lobes. 


Lobe- 
length. 


Ratio  of 

lobe-length 

to  total 

length. 


Stig- 
ma tic 
portion, 
length. 


Append- 
age, 
length. 


Ratio  of 
appendage- 
length  to 
total  length 
of  branch. 


Subsp.  I.  consimilis — Cent. 

Shasta  Valley,  Calif 

Modoc  County,  Calif 

Near      Alturas,      Modoc 

County,  Calif 

Do 

Eastern  Oregon 

Average 


201306  UC 
195494  UC 

26511  Or 
193100  UC 
31187  UC 


Subspecies  m.  viridulm: 

Esmeralda  County,  Nev. . 

Lida,  Nev 

Mono  Lake,  Calif 

Near        Benton,       Mono 

County,  Calif 

Benton     Station,     Mono 

County,  Calif 

Benton,    Mono    County, 

Calif 

Do 

Deep  Spring,  Inyo  Coun- 
ty, Calif 

Laws,  Inyo  County,  Calif . 
Bishop,     Inyo      County, 

Calif 

Near      Bishop,      Inyo 

County,  Calif 

Eearsarge,   Inyo  County, 

CaUf 

Do 

Near     Kearsarge,      Inyo 

County,  Calif 

Independence,  Inyo 

County,  Calif 

Lone  Pine,  Inyo  County, 

Calif 

Do 

Panamint        Mountains, 

Inyo  County,  Calif.  . 
Average 


203071  UC 

203072  UC 
203067  UC 

203074  UC 

203077  UC 

203139  UC 
203134  UC 


203073  UC 
203131  UC 


203140  UC 
203075  UC 


203070  UC 
UC 


Subspecies  o.  mohavensit: 

Near  Mojave,  Calif 

Mojave  Desert,  Calif.  .  . 
Greenhorn       Mountains, 

Calif 

Alamo  Mountains,  Calif. 

Mt.  Hamilton,  Calif 

Near  Fort  Tejon,  Calif. . 

Mojave  Desert,  Calif.  .  . 

Average 


UC 

87255  UC 

63639  UC 

73921  UC 

177561  UC 

Gr 

Gr 


8.0 

7.8 
8.5 


10.0 
9.3 
9.5 
9.6 


8.5 
9.0 
9.0 


10.5 
9.6 

10.5 
9.8 
8.0 


p.ct. 
17.5 
17.6 


23.6 
23.3 
24.4 

23.5 

25.5 


31.9 
25.6 


22.8 
17.9 
21.9 
20.4 


21.7 


55.5 

65.5 
63.5 
68.0 


57.1 
66.7 
55.6 

53.8 

64.8 


60.0 
67.1 


54.6 
67.1 


0 

60.6 

7 

60.7 

1 

63.6 

7 

67.5 

1 

65.3 

8 

52.9 

6 

48.6 

'  Except  where  otherwise  mentioned  the  plants  selected  for  measurement  are  normal  and  fairly  representative  of  the  sub- 
species to  which  they  are  assigned.  The  figure  given  for  corolla  and  style  characters  is  the  average  of  a  number  of  measure- 
ments, but  the  fluctuation  usually  is  slight  on  any  given  plant.  The  involucre  is  more  variable.  Usually  several  of  the 
larger  and  fully  mature  involucres  were  selected  and  these  averaged.  The  measurement  is  from  the  base  of  the  lowest  row 
of  bracts  to  a  point  on  a  level  with  the  top  of  the  longest  bract,  assuming  the  involucre  to  be  in  a  vertical  position.  Thus 
no  allowance  was  made  for  the  slope  of  the  sides. 

•  Minor  variation  68,  C.  pulcherrimus  Nelson.  '  Type  of  C.  orihophyllus  Greene,  minor  variation  63. 

'  Minor  variation  58,  with  wide  and  thick  leaves.  '  Minor  variation  67,  C.  plaUensis  Greene. 

'  Minor  variation  57,  with  pubescence  covering  the  '  Type  of  C.  angitstue  Greene,  minor  variation  21. 

involucrea. 


234  GENUS   CHRYSOTHAMNUS. 

USES. 

The  value  of  this  shrub  as  a  browse  plant  for  animals  depends  largely  upon  local  con- 
ditions. Throughout  most  of  its  range  it  is  never  browsed,  except  under  very  unusual 
circumstances.  Toward  the  north,  however,  especially  in  Idaho  and  neighboring  States, 
the  stems  and  leaves  of  subspecies  speciosus  are  eaten  to  a  considerable  extent  by  sheep, 
according  to  reports  from  the  Forest  Service,  and  even  in  eastern  California  this  form 
is  sometimes  preferred  to  sagebrush  by  sheep.  In  northern  regions  it  furnishes  an 
important  winter  browse  for  elk  and  perhaps  also  for  moose.  On  the  other  hand,  reliable 
reports  indicate  that  this  species  is  poisonous  to  stock  under  certain  conditions,  at  least 
in  Nevada.  If  poisonous  at  all,  it  is  probable  that  serious  results  follow  only  when  it 
is  eaten  to  the  exclusion  of  other  foods,  or  when  the  animal  is  in  an  underfed  or  weakened 
condition. 

The  possible  utilization  of  Chrysothamnus  nauseosus  as  a  supply  of  rubber  has  been 
recently  investigated  by  Hall  and  Goodspeed  (Univ.  Calif.  Publ.  Bot.  7:183-264,  1919). 
Rubber  was  found  to  be  present  in  the  cortex  and  medullary  rays  in  all  of  the  12  varieties 
examined,  the  amount  present  running  as  high  as  6.57  per  cent  in  individual  plants, 
but  averaging  only  2.83  per  cent  even  for  the  best  variety.  The  most  constant  producers 
were  the  varieties  inhabiting  alkaline  soils,  especially  viridulus,  consimiJis,  pinifolius, 
and  turhinatus.  Field  surveys  indicated  that  perhaps  300,000,000  pounds  of  rubber 
of  good  grade  are  present  in  the  wild  shrub  of  this  species  in  the  western  United  States 
and  that  this  supply  could  be  drawn  upon  in  case  of  a  national  emergency,  such  as  an 
extensive  war  during  which  time  overseas  importations  might  be  curtailed.  The  per- 
centage content  of  the  shrub  is  much  too  low  to  render  the  extraction  of  the  rubber  a 
profitable  undertaking  under  normal  conditions.  Even  in  wartime  the  total  amount 
obtainable  would  be  insufficient  for  more  than  a  supplementary  supply.  It  would  seem 
wise,  therefore,  to  carry  the  investigation  of  this  and  other  rubber  plants  still  further 
in  the  hope  of  so  increasing  the  yield  through  breeding,  selection,  and  various  other 
methods  of  treatment  that  a  permanent  rubber-growing  industry  could  be  established 
within  the  boundaries  of  the  continental  United  States. 

The  herbage  of  certain  subspecies,  notably  hohleucus  and  gnaphalodes,  is  so  pleasantly 
fragrant  that  the  preparation  of  an  essential  oil  from  it  would  seem  to  be  among  the 
possibilities. 


Explanations  of  Plates  24  to  35,  Genus  Chrysothamnus. 


Plate  !24. 

Chrysothamnus  paniculatus.  (Drawn  from  fresh  material 
from  east  side  of  Tehachapi  Pass,  Calif.) 

(1)  Portion  of  the  inflorescence,  X  1. 

(2)  Habit  sketch  of  an  old  plant,  woody  through- 

out, X  0.03. 

(3)  Surface  view  of  the  middle  portion  of  a  leaf 

to  show  the  resin-pits,  X  20. 

(4)  Head,  X  3. 

(5)  Outer  bract  of  the  involucre,  X  9. 

(6)  Inner  bract,  X  9. 

(7)  Flower  with  part  of  pappus  removed,  X  6. 

(8)  Style-branches,  X  12. 

(9)  Anthers,  X  12. 

Chrysothamnus  teretifolius.     (Material  from  Inyo  and 
Kem  Counties,  Calif .,  32917  and  194530  UC.) 

(10)  Branch  showing  leaves  and  inflorescences,  X  1. 

(11)  Branch  with  a  narrow  mflorescence,  X  1. 

(12)  Sketch    of    plant    growing    among    rocks    at 

Benton,  California,  X  0.05. 

(13)  Head  showing  thickened  tips  to  the  bracts,  X  3. 

(14)  Outer  bract  of  the  mvolucre,  X  9. 

(15)  Inner  bract,  X  9. 

(16)  Flower  with  part  of  pappus  removed,  X  6. 

(17)  Style-branches,  X  12. 

(18)  Anthers,  X  12. 

(19)  Surface  view  of  the  middle  portion  of  a  leaf 

to  show  the  resin-pits,  X  20.     (See  fig.  24o, 
p.  160,  for  cross-section.) 
Plate  25. 

Chrysothamnus   gramineus.     (Drawn    from    the    type 
specimen.) 

(1)  Upper  portion  of  the  stem  showing  the  arrange- 

ment of  the  heads  and  the  broad  leaves,  X  1. 

(2)  Head  showing  the  broad  truncate  bracts,  X  3. 

(3)  Outer  bract  of  the  mvolucre,  X  9. 

(4)  Inner  bract,  X  9. 

(5)  Flower   with   part   of   pappus    removed   and 

showing  elongated  glabrous  achene,  X  6. 

(6)  Style-branches  showing  the  very  short  stig- 

matio  portion  and  the  long  appendages,  X  12 

(7)  Anthers,  X  12 

(8)  Habit  sketch  showing  part  of  plant,  X  0.12. 
Chrysothamnus    vaseyi.       (Material    from    Panguitch 

Lake,  Utah,  159879  UC.) 

(9)  Portion  of  plant  showing  the  erect  leafy  shoots 

and  the  inflorescences,  X  1. 
(10)  Head,  X  3.      The    bracts    are    greenish    and 

slightly  thickened  near  the  tip. 
(U)  Outer  bract  of  the  involucre,  X  9. 

(12)  Inner  bract,  X  9. 

(13)  Flower  with  a  portion  of  the  pappus  removed 

and  showing  the  short  glabrous  achene,  X  6. 

(14)  Style-branches  showing  the  elongated  stigmatic 

portion  and  the  short  appendages,  X  12. 

(15)  Anthers,  X  12. 
Plate  26. 

Chrysothamnus    viscidiflorus    lanceolatus.       (Material 
from  Cerro  Sunmiit,  Colorado,  55164  UC.) 

(1)  Branch  showing  leaves  and  inflorescence;  herb- 

age puberulent;  X  1. 
Chrysothamnus  msddiflorus  puberulus.    (Material  from 
Northern  Nevada,  175448  UC.) 

(2)  Branch    showing    leaves    and    inflorescences; 

herbage  puberulent;  X  1. 

(3)  Head,  X  3. 

(4)  Outer  bract  of  the  involucre,  X  9. 

(5)  Inner  bract,  X  9. 

(6)  Flower  with  part  of  pappus  removed,  X  6. 

(7)  Style,  X  12. 

(8)  Anthers,  X  12. 


Plate  26 — continued. 
Chrysothamnus   viscidiflorus   humilis.      (Drawn   from 
material  of  the  type  collection,  87252  UC.) 
(9)  Portion  of  plant  showing  leaves  and  inflores- 
cences; herbage  puberulent;  X  1. 
Chrysothamnus  visddifiorus  elegans.     (Material  from 
Gunnison  Valley,  Colorado,  193530  UC.) 

(10)  Summit  of  branch  with  inflorescence;  herbage 

puberulent;  the  leaves  in  this  and  other  sub- 
species may  be  either  twisted,  as  here  shown, 
or  straight,  bracts  greenish-tipped;  X  1. 
Chrysothamnus  viscidiflorus  stenophyllus.    (Drawn  from 
specimen  of  type  collection,  Watson  566,  NY.) 

(11)  Summit  of  branch  with  inflorescence;  herbage 

glabrous;  X  1. 
Chrysothamnus  viscidiflorus  pumilus.     (Material  from 
Pocatello,  Idaho,  193103  UC.) 

(12)  Summit  of  branch,  wath  inflorescence;  herbage 

glabrous;  X  1. 
Plate  27. 

Chrysothamnus  viscidiflorus  Unifolius.     (Drawn  from 
fresh  material  from  Point  of  Rocks,  Wyo.) 

(1)  Leafy   stem  and  inflorescence;    herbage  glab- 

rous; X  1. 

(2)  Head  showing  the  slightly  thickened  greenish 

tips  to  the  bracts  of  the  involucre,  X  3. 
Chrysothamnus    viscidiflsrus    typicns.      (Drawn    from 
material  from  Weber  Caiion,  Utah,  preserved 
in  hquid.) 

(3)  Inflorescence  and  leaves;  glabrous;  X  1. 

(4)  Head,  X  3. 

(5)  Outer  bract  of  the  involucre,  X  9. 

(6)  Inner  bract,  X  9. 

(7)  Flower  with  part  of  pappus  removed,  X  6. 

(8)  Style-branches,  X  12. 

(9)  Habit-sketch    of    a    plant    at    Buena    Vista, 

Colorado;  X  0.1. 
Plate  28. 

Chrysothamnus  greeneifilif alius.      (Material  from  Lund, 
Utah,  203159  UC.) 

(1)  Leafy  shoot  with  inflorescence,  X  1. 

(2)  Anthers,  X  12. 

(3)  Head,  X  3. 

(4)  Outer  bract  of  the  involucre,  X  9. 

(5)  Inner  bract,  X  9. 

(6)  Flower  with  part  of  pappus  removed,  X  6. 

(7)  Style-branches,  X  12. 

Chrysothamnus  albidus.     (Drawn  from  fresh  material 
from  the  type  locality.) 

(8)  Leafy  shoot  with  inflorescence,  X  1. 

(9)  Habit  sketch  of  a  plant  growing  on  an  alkaU 

flat;    C.    nauseosus    consimilis    and    Elymua 
condensatus  in  the  background;  X  0.05. 

(10)  Surface  view  of  middle  part  of  leaf  to  show  resin- 

pits,  X  20.  (See  fig.  246,  p.  160,  for  cross-section.) 

(11)  Anthers,  X  12. 

(12)  Flower  with  a  portion  of  the  pappus  removed; 

the  curved  corolla  is  characteristic;  X  6. 

(13)  Outer  bract  of  the  involucre,  X  9. 

(14)  Inner  bract,  X  9. 

(15)  Style,  X  12. 

(16)  Head,  X  3. 
Plate  29. 

Chrysothamnus    pulchellus    typicus.     (Material    from 
Chihuahua,  87217  UC.) 

(1)  Branch,  X  1. 

(2)  Outer  bract  of  the  involucre,  X  9. 

(3)  Inner  bract,  X  9. 

(4)  Habit  sketch  of  a  plant  growing  in  northwestern 

New  Mexico,  X  0.1. 


Explanations  of  Plates  24  to  35,  Genus  Chrysothamnus. 


Plate  29 — continued. 

(5)  Head,  X  3. 

(6)  Flower  with  part  of  pappus  removed,  X  6. 

(7)  Anthers,  X  12. 

(8)  Style,  X  12. 

Chrysothammts  depressus.     (Drawn  from  fresh  material 
from  northern  Arizona.) 

(9)  Branch,  X  1. 

(10)  Head,  X  3. 

(11)  Flower  with  a  part  of  pappus  removed,  X  6. 

(12)  Cute*  bract  of  the  involucre,  X  9. 

(13)  Inner  bract,  X  9. 

(14)  Style,  X  12. 
Plate  30. 

Chrysothamnus  pyramidalus.     (Drawn  from  material 
collected  above  Oaxaca,  Mexico,  87304  UC.) 

(1)  Branch   showing   the   characteristic   fascicled 

leaves  and  the  raceme-hke  inflorescence,  X  1 . 

(2)  Head  showing  the  loosely  arranged  bracts,  X  3. 

(3)  Accessory   bract   from   just   beneath   the   in- 

volucre, X  9. 

(4)  Outer  bract  of  the  involucre,  X  9. 

(5)  Inner  bract,  X  9. 

(6)  Flower  with  part  of   pappus    removed,  X  6. 

(7)  Style-branches,  X  12. 

(8)  Anthers,  X  12. 
Chrysothamnus  parryi  laiior. 

(9)  An  erect  stem  showing  the  broad  leaves  and 

the  inflorescence,  X  1. 
Plate  31. 
Chrysothamnus  parryi  typicus.      (Main   drawing  from 
fresh  material  from   San   Juan    Mountains, 
Colorado,  205815  UC;  the  details  are  from  a 
plant    collected    at    Leadville,   Colorado.) 

(1)  Erect  flowering  stem  showing  ample  foliage,  X  1. 

(2)  Style-branches    showing    the    elongated    ap- 

pendages, X  12. 

(3)  An  outer  bract  of  the  involucre,   X  9.     Inner 

bracts  less  attenuate,  as  shown  in  fig.  6. 

(4)  Anthers,  X  12. 

(5)  Flower  with  part  of  pappus  removed,  X  6. 

(6)  Head  showing  the  loose  arrangement  of  the 

involucral  bracts,  X  3. 
Chrysothamnus    parryi    imultis.     (Drawn    from    the 
type  specimen.) 

(7)  Portion  of  a  plant  showing  the  low  spreading 

habit,  X  1. 

(8)  Anthers,  X  12. 

(9)  Flower  with  part  of  pappus  removed,  X  6. 

(10)  Outer  bract  of  the  involucre,  X  9. 

(11)  Inner  bract,  X  9. 

(12)  Head,  X  3. 

(13)  Style-branches    showing    the    elongated    ap- 

pendages, X  12. 
Plate  32. 

Chrysothamnus  parryi  vulcanicus. 

(1)  Inflorescence  and  upper  leaves,  X  1.    (Material 

from  the  southern  Sierra  Nevada,  California, 
126456  UC.) 

(2)  A  narrower  inflorescence,  X  1.    (Material  from 

upper  San  Joaquin  River,  Calif.,  87221  UC.) 
Chrysothamnus  parryi  nevadensis.    (Material  from  near 
Verdi,  Nevada,  193101  UC.) 

(3)  Inflorescence  and  upper  leaves,  X  1. 
Chrysothamnus  parryi  asper.     (Material  from  Charles- 
ton Mountains,  Nevada,  171476  UC.) 

(4)  Inflorescence    and    upper    leaves,    the    latter 

rough-pubescent  with  stalked  glands;  X  1. 
Chrysothamnus   parryi  howardi.     (Drawn  from   fresh 
material  from  near  Buena  Vista,  Colorado.) 

(5)  Upper  portion  of  plant  with  inflorescences,  X  1. 


Plate  32 — continued. 

(6)  Head,  X  3. 

(7)  Style,  X  12. 

(8)  Flower  with  part  of  pappus  removed,  X  6. 

(9)  Outer  bract  of  the  involucre,  X  9. 

(10)  Inner  bract,  X  9. 

(11)  Anthers,  X  12. 
Plate  33. 

Chrysothamnus  nauseosus  speciosu^. 

(1)  Branch  and  inflorescence  of  a  form  with  broad, 

heavy  leaves  (minor  variation  58,  p.  221); 
X  1.  (Material  from  Honey  Lake  Valley, 
northeastern  Cahfomia.) 

(2)  Leaf  and  heads  of  robust  form  (minor  variation 

68,  p.  222,  C.  pulcherrimus),  X  1.  (Mate- 
rial from  Woods  Landing,  Wyo.,  10662  R.) 

(3)  Leafy    shoot    and    inflorescence    of    typical 

speciosus,  X  1.  (Material  from  Crater  Lake, 
Oregon,  20317  UC.) 
Chrysothamnus  nauseosus  gnaphalodes.  (Drawn  from 
living  material  in  the  Botanical  Garden  of 
the  University  of  California,  grown  from  seed 
collected  at  Benton,  Cahfomia;  fig.  5  from 
a  photograph  taken  at  Benton.) 

(4)  Leafy  branch  and  inflorescence,  X  1. 

(5)  Habit  sketch  of  a  normally  developed  plant 

of  sandy,  well-drained  soil;  X  0.04. 

(6)  Head,  X  3. 

(7)  Outer  bract  of  the  involucre  showing  the  woolly 

pubescence,  X  9. 

(8)  Inner  bract,  woolly  on  the  exposed  tip;  X  9. 

(9)  Flower  with  a  portion  of  the  pappus  removed 

showing  the  pubescent  corolla-tube  and  the 
very  short  corolla-lobes,  X  6. 

(10)  Anthers,  X  12. 

(11)  Style-branches  showing  the  very  short  appen- 

dages, X  12. 
Plate  34. 

Chrysothamnus  nauseosus  typicus. 

(1)  A  branch  of  the  genuine  form  from  Laramie, 

Wyoming  (July  29,  1889,  Greene,  UC, 
labeled  C./nsidus),  X  1. 

(2)  A    branch   with   longer   and   slightly    curved 

leaves  (minor  variation  76,  p.  222,  C.  speciosus 
plattensis),  X  1.  (Drawn  from  fresh  material 
from  East  Denver,  Colorado.) 

(3)  A  more  widely  branched  inflorescence  from  the 

same  collection  as  2,  X  1. 

(4)  Head  from  the  branch  shown  in  3,  X  3. 

(5)  Outer  bract  of  involucre  of  same  head,  X  9. 

(6)  Inner  bract  of  the  same  involucre,  X  9. 

(7)  Style-branches    of    the    flower    figured    in  9, 

showing  the  long  appendages,  X  12. 

(8)  Anthers  from  the  same  flower,  X  12. 

(9)  Flower  from  the  head  shown  in  4,  a  portion  of 

the  pappus  removed;  X  6. 
(10)  Habit  sketch  of  a  plant  growing  near  Laramie, 
Wyoming;  X  0.08. 
Plate  35. 
Chrysothamnus  nauseosus  graveolens.      (Drawn   from 
fresh  material  and  photographs  from  eastern 
Colorado.) 

(1)  Inflorescence  and  upper  leaves,  X  1. 

(2)  Habit  sketch  of  normal  plant  of  good  soils, 

more  spreading  and  regular  in  outline  than 
in  most  specimens;  X  0.03. 

(3)  Flower  with  part  of  pappus  removed,  X  6. 

(4)  Style,  X  12. 

(5)  Anthers,  X  12. 

(6)  Outer  bract  of  the  involucre,  X  9. 

(7)  Inner  bract,  X  9. 

(8)  Head,  X  3. 


HALL  AND  CLEMENTS 


41M 


^h  ^fex 


M 


mm,     W  ' 


4 


15     < 


\ 


M 


14 


13  '^^' 


18 


11 


L<.' 


12 


11 


ffu(A  J.  Poueli  dd. 


Chiysothamnu?  paiiiculatus.  figs.  1  to  9. 


Chrvsothaninus  teretifolius.  figs.  10  to  19. 


HALL  AND  CLEMENTS 


Chrysothamnus  gramineus,  figs.  1  to  8.  Chrysothamnus  vaseyi,  figs.  9  to  15. 


HALL  AND  CLEMENTS 


ulh   ./.   Pmeell  A 


Chrysothamnus  viscidiflorus  lant-eolatus.  fig.  1.  Chrysothaninus  viscidiflorus  elegans,  (ig.  10. 

Chrysothamnus  viscidiflorus  puberulus,  figs.  2  to  8.     Chrysttthamnus  viscidifloiiis  .stenophyllus,  fig.  11. 
Chrysothamnus  viscidiflorus  humilis,  fig.  9.  Chrysothamnus  viscidiflorus  pumikis,  fig.  12. 


HALL  AND  CLEMENTS 


mm 


^ 


,^v.K^^'V.r^w^%^^^ 


~^\ 


1^,:r;i 


%f  "  ■ 


W< 


..V;^ 


^^.    ^  eV 


Ruth  J.  Powell  M. 

Chrysothamnus  viscidiflorus  linifolius,  figs.  1  and  2.  Chrysothamnus  viscidiflorus  typicus,  figs.  3  to  9. 


HALL  AND  CLEMENTS 


Ruth  J.   Powell  del. 

Chrysothamnus  greenei  filil'olius.  figs.  1  to 


Chi\s(jthamiiu.s  albidus,  ligs.  8  to  16. 


HALL  AND  CLEMENTS 


Ruth  J.  Powell  lid. 

Chrysothamnus  pulchellus  typicus.  figs.  1  to  8. 


Chrysothamnus  depressus,  figs.  9  to  11. 


HALL  AND  CLEMENTS 


iilh  J.  Pourll  del. 

Chrysothamnus  pyramidatus,  figs.  1  to  8.  Chrysothaninus  parryi  latior,  fig.  9. 


HALL  AND  CLEMtNTS 


Riilli  J.   Pou-ell  M. 


Chrysothaninus  parryi  typicus.  figs.  1  to  6.  Chrysothaninus  parryi  imulus,  figs.  7  to  13. 


Riilh  ./.   Pouell  del. 

Chrysothamnus  pariyi  vulcanicus,  figs.  1  and 
Chrysothamnus  parryi  nevadensis,  fig.  3. 


Chrysothamnus  parryi  asper,  fig.  4. 
Chrysothamnus  parryi  howardi,  figs.  5  to  11. 


Rull,   J.   P„mll   . 


Chrvsothamnus  nauseosus  speciosus.  figs.  1  to  3.  Chrysothamnus  nauseosus  gnaphalodes,  figs.  4  to  11. 


HALL  AND  CLEMENTS 


i^M:fM,, 


Rvth  J.  PouM  del. 


Chiysolhaniruis  nauscosus  typicus. 


HALL  AND  CLEMENTS 


Ruth  J.  Powell  del. 


Chrysothamnus  nauseosus  graveolens. 


GENUS  ATRIPLEX 

HISTORY  AND  GENERIC  LIMITS. 

Up  to  recent  times  the  history  of  the  genus  Atriplex  has  been  one  of  taxonomic  segre- 
gation. According  to  many  pre-Linnaean  botanists,  it  included  practically  all  of  what  is 
known  as  the  family  Chenopodiaceae,  and  apparently  even  a  few  species  of  Polygonaceae 
found  their  way  into  the  genus.  Linnaeus  drew  the  generic  lines  much  more  closely, 
following  in  this  respect  a  growing  tendency  among  European  taxonomists.  Thus  there 
came  to  be  established  by  the  middle  of  the  eighteenth  century  such  well-known  genera 
as  Chenopodium,  Beta,  Spinachia,  Blitum,  and  Salsola. 

After  the  time  of  Linnaeus  there  was  no  further  division  of  the  genus  until  1791, 
when  Gaertner  described  Ohione  (Gaertner,  Fruct.  2:198),  with  a  single  species,  0. 
muricata  {  =  Atriplex  siberica  Linnaeus).  This  genus  was  accepted  by  Moquin-Tandon 
in  his  monograph  of  the  Chenopodiaceae  (Chenopodearum  monographica  enumeratio 
1840),  and  to  it  have  been  referred  a  majority  of  the  American  species  now  included 
under  Atriplex.  The  single  constant  character  of  Ohione  is  the  inverted  embryo,  the 
radicle  of  which  thus  comes  to  assume  a  superior  position  in  relation  to  the  plumule. 
The  importance  of  this  character  of  the  embryo  is  fundamental.  By  reference  to  the 
chart  of  relationships  (fig.  29,  p.  238)  it  will  be  seen  that  it  is  used  in  the  present  treat- 
ment as  indicating  the  phylogenetic  separation  of  all  of  the  American  Atriplexes  into 
two  principal  stocks,  or  subgenera.  However,  its  acceptance  as  a  generic  criterion 
sunders  groups  of  close  affinity,  with  the  result  that  the  relationships  between  them  are 
no  longer  expressed.  Furthermore,  there  is  no  positive  evidence  that  the  result  is  a 
natural  classification.  For  example,  while  it  is  probable  that  A.  rosea  and  A.  argentea, 
the  former  a  true  Atriplex,  the  latter  an  Ohione,  have  been  derived  from  widely  separate 
stocks,  yet  they  are  so  closely  alike  in  many  features  that  their  distribution  into  distinct 
genera  is  likely  to  be  misleading.  It  is  possible  that  these  are  no  more  widely  separated 
from  each  other  phylogenetically  than  either  of  them  is  from  A.  hortensis  or  from  A. 
patula.  As  far  as  the  American  species  are  concerned,  this  character  serves  for  the 
primary  division  of  the  genus  better  than  any  other,  and  therefore  it  is  used  as  a  basis 
for  the  recognition  of  two  subgenera.  In  one  introduced  species,  namely,  A.  semi- 
baccata,  the  radicle  lies  to  one  side  of  the  embryo.  Such  lateral  radicles,  which  occur 
in  a  number  of  other  foreign  species  as  well,  may  be  taken  as  representing  an  intermediate 
stage,  the  presence  of  which  greatly  weakens  the  status  of  Ohione  as  a  genus.  It  is 
retained  by  a  few  European  botanists,  e.  g.,  Ascherson  and  Graebner  (Syn.  Mitteleur. 
Fl.  5:109,  1913),  but  it  was  not  given  generic  standing  by  Bentham  and  Hooker  (Gen. 
PI.  3:54,  1880)  nor  by  Volkens  (in  Engler  and  Prantl,  Natiirl.  Pflanzenfam.  3'":  64, 
1893),  nor  by  Moss  and  Willmott  (in  Moss,  Cambridge  Brit.  Fl.  2: 168, 1914).  In  America 
Ohione  was  accepted  as  a  genus  by  Torrey  but  not  by  Nuttall,  Gray,  nor  any  of  the  more 
recent  writers.  Watson  treated  it  as  a  genus  in  his  Report  on  the  Botany  of  the  King 
Exploration  of  the  Fortieth  Parallel  (1871),  but  when  he  came  to  his  revision  of  the 
North  American  Chenopodiaceae  (Proc.  Am.  Acad.  9:82-126,  1874)  he  reduced  Ohione 
into  Atriplex. 

The  next  generic  proposal  was  Pterochiton  Torrey  and  Fremont  (in  Fremont,  Rep.  Rocky 
Mts.  Ore.  Calif.  318,  1845).  This  was  based  upon  a  form  now  referred  to  A.  canescens. 
Its  most  distinguishing  feature  is  the  development  of  4  pronounced  wings  to  the  fruiting 
bracts.  Aside  from  the  fact  that  bract  characters  are  of  doubtful  value  as  a  basis  for 
genera,  it  is  to  be  noted  that  in  this  case  the  wings  are  sometimes  simulated  by  flattened 
appendages  in  other  groups.  Furthermore,  certain  specimens  to  be  mentioned  under 
A.  canescens  are  either  intermediate  in  this  respect  or  are  hybrids  between  some  genuine 

235 


236  GENUS   ATRIPLEX. 

species  of  Atriplex  and  A.  canescens.  Pterochiton  was  recognized  by  Nuttall  (Jour. 
Acad.  Phila.  II,  1:184,  1848),  but  otherwise  it  has  been  considered  as  not  more  than 
a  section  or  subgenus  of  Atriplex. 

Endolepis  was  proposed  by  Torrey  (in  Gray,  Pacif.  R.  R.  Rep.  12^47,  1860)  on  the 
basis  of  a  peculiarly  shaped  perianth  in  the  staminate  flowers  and  the  presence  of  a 
calyx  in  the  pistillate  flowers.  But  a  calyx  is  sometimes  present  even  in  the  type  species 
of  Atriplex  (A.  hortensis).  It  will  be  demonstrated  under  A.  phyllostegia  (p.  267)  that  this 
structure  is  vestigial  and  that  in  at  least  one  species  it  may  be  found  in  all  stages  of  sup- 
pression. Therefore,  its  presence  or  absence  can  not  be  used  for  the  separation  of  genera. 
Endolepis  was  merged  into  Atriplex  by  Watson  in  his  revision  of  the  family  above  referred 
to.  Recently  it  has  been  revived  as  a  genus  by  Rydberg  (Bull.  Torr.  Club  30:248, 
1903)  and  by  Standley  (N.  Am.  Fl.  21:72,  1916),  while  Macbride  (Contr.  Gray  Herb, 
n.  s.  53:11,  1918)  insists  that  it  should  not  be  given  generic  standing. 

Additional  segregate  genera  have  been  proposed  by  European  botanists,  but  they 
include  no  American  species. 

None  of  the  above-mentioned  proposals  are  maintained  in  the  present  paper.  Instead, 
they  are  all  referred  to  the  genus  Atriplex,  which,  notwithstanding  their  inclusion, 
remains  a  natural  and  easily  defined  group.  But  in  order  to  maintain  this  unity  it  is 
necessary  to  exclude  one  segregate  formerly  referred  to  Atriplex.  This  is  the  genus 
Suckleya  Gray  (Proc.  Am.  Acad.  11:103,  1876),  based  upon  Obione  suckleyana  Torrey. 
This  is  a  nearly  prostrate  annual  herb  with  a  habit  unlike  that  of  any  true  Atriplex. 
Its  generic  standing  is  maintained  on  its  peculiar  fruiting  bracts,  which  are  strongly 
obcompressed,  i.  e.,  flattened  in  a  plane  contrary  to  that  of  the  original  position  of  the 
faces.  The  resulting  fruit  is  winged  dorsally,  but  these  wings  are  not  homologous  with 
the  four  prominent  wings  of  Pterochiton.  Suckleya  has  been  accepted  as  a  genus  by 
Bentham  and  Hooker,  by  Volkens,  and  by  all  of  the  more  recent  workers  on  the  group. 

The  American  species  of  Atriplex  have  received  monographic  treatment  by  but  three 
authors.  The  first  of  these  was  Moquin-Tandon,  who  published  his  Chenopodearum 
monographica  enumeratio  in  Paris  in  1840.  This  was  followed,  in  1849,  by  a  monograph 
by  the  same  author  in  De  Candolle's  Prodromus  (vol.  13,  part  2,  pp.  90  to  115)  where  98 
species  of  Atriplex  and  Obione  are  described,  this  number  comprising  all  of  the  species 
of  the  world  known  at  that  time.  As  indicated  above,  the  genera  just  mentioned  now 
constitute  the  two  subgenera  of  the  genus  Atriplex.  The  enormous  amount  of  labor 
involved  in  bringing  together  the  scattered  facts  regarding  the  genus  at  that  early  date, 
and  the  masterly  way  in  which  the  species  were  organized  and  described,  places  all 
later  workers  under  deep  obligation  to  this  early  specialist. 

No  account  covering  the  entire  genus  has  appeared  since  the  work  of  Moquin-Tandon. 
The  North  American  species,  however,  were  given  a  new  treatment  in  1874  by  Watson 
in  his  Revision  of  the  North  American  Chenopodiaceae  (Proc.  Am.  Acad.  9:82-126, 
1874).  Here  Obione  is  definitely  reduced  to  Atriplex,  which  is  then  divided  into  three 
sections,  the  first  comprising  annuals  with  the  radicle  inferior  or  subascending,  the 
second  annuals  with  the  radicle  usually  superior,  and  the  third  perennials  with  the 
radicle  usually  superior.  This  treatment  by  Watson,  which  includes  a  key  to  the  40 
accepted  species,  but  in  which  only  the  new  species  are  described,  has  served  as  a  basis 
for  all  accounts  given  in  regional.  State,  and  local  floras  up  to  1916.  In  this  year  there 
appeared  an  account  of  the  North  American  Chenopodiales  by  Standley  (N.  Am. 
Fl.  21:1-93).  Standley  follows  Watson  in  the  reduction  of  Obione  to  Atriplex,  but 
restores  Endolepis  as  a  distinct  genus,  to  which  3  species  are  referred.  His  account  of 
Atriplex  includes  103  species  grouped  into  29  sections.  The  comparatively  large  number 
of  species  recognized  is  due  in  part  to  the  adoption  of  a  narrow  species-concept;  in  part 
to  the  dependence,  as  it  seems  to  the  present  authors,  upon  certain  characters  since 


ORIGIN   AND    DEVELOPMENT   OF   THE    SECTIONS.  237 

found  to  be  too  variable  to  serve  as  taxonomic  criteria.  Other  revisions,  covering  por- 
tions of  North  America,  will  be  found  in  the  various  floras.  The  most  notable  of  the 
recent  contributions  of  this  nature  will  be  found  in  Jepson's  Flora  of  California  (pp.  433 
to  442,  1914)  and  in  Rydberg's  Flora  of  the  Rocky  Mountains  and  Adjacent  Plains 
(pp.  245  to  250,  1917). 

The  present  authors  have  greatly  benefited  from  the  monographs  and  revisions  just 
enumerated.  Especial  attention,  however,  has  been  given  to  the  assembling  of  pre- 
viously unknown  facts  regarding  the  plants,  more  particularly  through  field  studies 
and  cultural  experiments.  The  result  is  that  the  forms  can  now  be  more  accurately 
described  and  their  phylogeny  worked  out  in  a  manner  much  more  satisfactory  than 
was  previously  possible. 

ORIGIN  AND  DEVELOPMENT  OF  THE  SECTIONS. 

The  American  species  of  Atriplex  can  not  be  assembled  into  natural  groups  and  the 
origin  of  these  satisfactorily  determined  until  those  of  other  parts  of  the  world  have 
also  been  studied  in  some  detail.  Therefore,  aside  from  the  two  subgenera  almost 
universally  accepted,  no  formal  classification  into  sections  will  be  here  presented.  The 
group  names  proposed  by  Standley  (N.  Am.  Fl.  21:33-72,  1916)  will  be  sometimes  used 
for  convenience,  as  will  also  other  sectional  and  subgeneric  names  which  have  been 
proposed  by  European  workers  without  much  regard  to  American  forms. 

The  primitive  stock  from  which  Atriplex  has  developed  was  almost  certainly  of  a 
type  in  which  the  radicle  pointed  downward  in  the  embryo  and  in  which  the  essential 
organ  of  the  pistillate  flower  was  subtended  by  some  sort  of  a  perianth.  The  inferior 
position  of  the  radicle  is  so  common  in  the  Chenopodiales  that  any  modification  from  this 
indicates  a  divergent  phylogenetic  line.  Similarly  the  absence  of  a  perianth  is  looked 
upon  as  a  case  of  suppression  and  therefore  a  mark  of  advance.  With  these  postulates 
in  mind  it  becomes  impossible  to  select  any  one  Atriplex  as  the  common  ancestor.  The 
one  most  nearly  meeting  the  requirements  is  A.  hortensis,  the  taxonomic  type  of  the 
genus.  Therefore,  this  species  is  placed  at  the  beginning  of  the  subgenus  Euatriplex, 
i.  e.,  the  branch  in  which  the  radicle  is  always  inferior  and  the  perianth  either  present 
or  absent  in  the  pistillate  flowers.  In  the  only  other  subgenus,  namely  Obione,  the 
embryo  always  is  inverted,  so  that  the  radicle  points  upward  (superior)  and  a  much 
reduced  perianth  is  found  only  in  a  few  primitive  species. 

Of  the  American  species  of  Euatriplex  only  hortensis,  itself  introduced,  exhibits  a 
true  perianth  in  the  pistillate  flowers.  Even  here  a  partial  suppression  has  taken  place, 
since  only  a  portion  of  the  flowers  possess  this  structure.  This  species,  together  with 
a  few  minor  derivatives,  comprises  the  section  Dichospermum  Dumortier.  Next  to 
hortensis,  but  probably  not  a  derivative  from  it,  comes  the  section  Teutliopsis  Dumortier, 
which  includes  A.  patula  (section  Hastatae  Standley)  with  a  long  series  of  subspecies 
and  minor  variations  widely  distributed  in  both  hemispheres.  It  has  a  perianth  only 
in  the  staminate  flowers  and  has  developed  features  of  the  bracts  which  are  quite  dis- 
tinctive. The  absence  of  fusion  between  the  bracts  in  some  of  the  forms  and  the  lack  of 
complete  fusion  in  any  of  them  may  be  taken  as  indicating  a  low  stage  of  development, 
while  other  considerations,  especially  the  wide  distribution  and  the  abundance  in  a  large 
variety  of  ecologic  habitats,  indicate  this  as  a  very  successful  type. 

Atriplex  calif ornica  is  placed  near  to  patula  in  the  phylogenetic  chart,  but  probably 
its  connections  are  much  more  primitive.  Its  position  is  very  doubtful  as  will  be  explained 
in  discussing  its  relationships  (p.  257).  Also,  A.  semibaccata  and  A.  halimoides,  two  species 
introduced  from  Australia  and  doubtless  of  a  very  different  alliance,  are  given  place  in 
the  taxonomic  sequence  as  a  matter  of  convenience.  In  the  former  the  radicle  is  lateral, 
rather  than  inferior,  suggesting  a  connection  with  the  subgenus  Obione. 


238 


GENUS   ATRIPLEX. 


Fio.  29. — Phylogenetic  chart  oi  the  subgenera  and  smaller  divisions  of  Alriplcx.  The  relative  size  oi  the  circlesTjhafi  no 
significance.  Large  groups  of  species  are  sometimes  indicated  by  small  circles  in  order  to  bring  the  whole  chart 
within  the  limits  of  the  page.  Tnese  groups  are  diagrammed  in  detail  as  follows:  group  of  A.  puaitlus,  fig.  33, 
p.  270;  group  of  .4.  truncata.  fig.  35,  p.  278;  group  of  A.  pentandra,  fig.  39,  p.  294;'group  of  dioecious  shrubs,  fig. 
43,  p.  314. 


ORIGIN   AND    DEVELOPMENT   OF   THE    SECTIONS.  ZdV 

The  rosea  group,  consisting  of  three  important  species  introduced  from  Europe,  has 
had  a  development  corresponding  to  that  of  patula.  But  here  the  fruiting  bracts,  instead 
of  remaining  soft  have  become  more  hardened  and  cartilaginous  than  in  any  other 
group.  For  this  reason  the  name  Sclerocalymna  was  proposed  for  the  section  by 
Ascherson.  The  similarity  to  other  sections  is  expressed,  on  the  other  hand,  by  the 
taxonomically  equivalent  name  of  Obionopsis  Lange.  The  shape  as  well  as  the  degree 
of  induration  of  the  fruiting  bracts  is  closely  approximated  in  some  forms  of  A.  argentea 
and  other  members  of  Obione. 

The  most  primitive  American  representatives  of  the  subgenus  Obione  are  A.  dioeca 
and  A.  monilifera.  They  belong  to  the  so-called  genus  Endolepis  Torrey,  which,  how- 
ever, is  better  received  as  a  section  of  Airiplex.  A  much  reduced  but  evident  perianth 
is  present  in  the  pistillate  flowers  of  these  species,  as  also  in  those  of  the  closely  related 
A.  phyllostegia.  In  this  last,  however,  the  perianth  sometimes  is  completely  suppressed, 
as  it  is  in  all  of  the  succeeding  species  of  Airiplex. 

In  order  to  arrange  the  remaining  species  in  their  proper  phylogenetic  sequence,  it  is 
necessary  first  to  determine  the  evolutionary  significance  of  the  characters  which  dif- 
ferentiate them.  Of  these,  the  development  of  dioecism  and  of  the  shrubby  habit  seem 
to  be  the  most  important.  There  are  no  dioecious  species  in  Euatriplex.  In  Obione 
the  tendency  toward  a  complete  separation  of  the  sexes  is  noted  at  a  number  of  places, 
especially  in  the  species  phyllostegia  and  powelli.  Complete  dioecism  is  attained,  how- 
ever, only  in  the  truly  shrubby  species  and  two  herbaceous  ones,  namely,  decumbens  and 
matamorensis.  The  nearly  complete  parallelism  between  these  two  characters  is  assumed 
to  justify  their  use  as  criteria  for  the  assembling  of  the  large  number  of  species  into  two 
natural  groups — the  group  of  monoecious  herbs  and  the  group  of  dioecious  shrubs. 
The  two  notable  exceptions  just  mentioned  form  an  intermediate  group  marked  also 
by  its  opposite  leaves,  an  almost  unique  feature  in  the  genus.  The  transition  between 
the  group  of  monoecious  herbs  to  that  of  the  dioecious  shrubs  is  found  in  some  members 
of  the  pentandra  subgroup  with  woody  basal  portions  and  in  "shrubby"  species  {bar- 
clayana,  acanthocarpa,  corrugata)  which  are  sometimes  herbaceous  nearly  to  the  base. 
Of  these  latter,  A.  barclayana  is  but  imperfectly  dioecious,  since  at  least  a  few  fruiting 
bracts  may  be  found  on  many  of  the  pistillate  plants.  The  connection  between  the 
pentandra  group  and  barclayana  is  suggested  also  by  the  turgid  bracts  in  certain  forms 
of  each  and  by  striking  similarities  in  other  features.  The  trait  of  monoecism  persists 
also  in  A.  lentiformis,  a  truly  shrubby  species,  for,  although  the  individuals  of  this  are 
for  the  most  part  either  chiefly  staminate  or  chiefly  pistillate,  plants  are  not  rare  on 
which  the  sexes  are  about  equally  represented.  Occasional  monoecism  is  found  also  in 
other  shrubby  species. 

The  derivation  of  the  dioecious  shrubby  Atriplexes  from  a  stock  close  to  the  pentandra 
group,  as  just  proposed,  may  appear  to  start  them  off  too  far  along  in  the  phylogenetic 
sequence.  It  should  be  noted,  however,  that  while  this  gives  them  a  high  position  on 
the  chart  of  relationships  (fig.  29,  p.  238),  it  is  possible  that  pentandra  itself  may  be 
more  primitive  than  might  be  assumed  from  its  location.  The  evolutionary  line,  as 
charted  in  the  diagram,  does  not  pass  through  any  group  above  Endolepis,  so  that  the 
pentandra  group  may  be  considered,  if  so  desired,  as  no  higher  in  the  scale  than  the 
others,  each  of  which  terminates  a  divergent  line.  A.  pentandra  may  be  even  basal  to 
these  others,  as  its  center  of  distribution  in  Mexico  would  seem  to  indicate,  but  the 
tendency  to  an  obovate  shape  of  the  fruiting  bracts,  which  is  a  reversal  of  the  usual 
leaf  and  bract  shape,  and  the  separation  of  the  sexes  into  different  inflorescences,  which 
presages  the  dioecism  of  the  shrubby  species,  furnish  evidence  opposed  to  this  view. 

Atriplex  pusilla  and  its  immediate  allies  form  a  natural  group  within  the  larger  assem- 
blage of  monoecious  herbs  of  the  subgenus  Obione.     All  are  annuals  with  fruiting  bracts 


240  GENUS   ATRIPLEX. 

widest  below  the  middle.  Next  to  these  comes  a  group  in  which  the  original  shape  of 
the  bracts  is  cuneate,  as  best  illustrated  in  A.  truncata.  But  in  two  of  the  species  (gra- 
ciliflora,  saccaria)  the  shape  is  so  modified  through  the  development  of  wing-like  margins 
or  appendages  that  the  clue  to  relationships  is  supplied  only  by  an  exceptional  unmodi- 
fied pair.  Close  to  these  species,  but  perhaps  even  closer  to  certain  of  the  Pusillae, 
is  the  small  group  of  A.  argentea  and  A.  coronata.  The  latter  has  fruiting  bracts  so  vari- 
able in  shape  that  it  is  often  confused  with  A .  cordulata  of  the  pusilla  group.  A .  powelli 
is  placed  by  itself  on  the  chart  because  of  its  semi-dioecious  habit,  as  already  noted,  and 
a  peculiar  shape  and  lobing  of  the  fruiting  bracts.  Probably  it  is  not  far  removed  from 
A.  argentea,  with  which  it  has  in  common  triple-nerved  leaves  and  other  vegetative 
features. 

Passing  over  the  groups  of  pentandra  and  decumbens,  which  have  been  already  discussed, 
there  remain  only  the  dioecious  shrubs.  There  is  abundant  evidence  that  these  had 
their  origin  far  to  the  south,  probably  in  Mexico.  Their  migrations  to  the  north  and 
northwest,  where  they  have  come  to  occupy  arid  saline  valleys  and  foothill  slopes,  were 
accompanied  by  considerable  modifications  in  habit  and  structure.  This  has  resulted 
in  the  development  of  11  species  and  a  much  larger  number  of  subspecies  and  minor  vari- 
ations. The  most  primitive  of  these,  as  indicated  by  their  partly  herbaceous  habit  and 
evident  connection  with  Mexican  forms  of  A .  pentandra,  are  A .  barclayana  and  the  group 
beginning  with  A.  acanthocarpa.  The  former  occupies  the  area  from  western  Sinaloa 
and  Sonora  across  Lower  California.  Evidence  as  to  its  former  connection  with  the 
monoecious  herbs  is  found  in  its  only  partial  dioecism,  in  the  herbaceous  branches,  and 
in  having  certain  subspecies  with  non-compressed  bracts.  A .  acanthocarpa  also  is  only 
a  subshrub.  Although  it  has  evolved  certain  features  of  its  own,  probably  it  best 
represents  the  ancient  stock  which  has  culminated  in  the  well-known  and  polymorphous 
A.  nuttalli,  a  species  which  has  reached  to  beyond  the  Canadian  boundary  in  its  north- 
ward migration. 

The  truly  shrubby  American  Atriplexes,  that  is,  those  in  which  even  the  twigs  are 
woody,  now  occupy  extensive  areas  in  the  Great  Basin  Region  and  westward,  a  few  of 
them  reaching  the  saline  shores  of  the  Pacific  in  California.  Beginning  near  A.  poly- 
carpa,  which  is  most  like  A .  barclayana  in  the  character  of  its  bracts,  each  has  developed 
features  so  unique  that  a  natural  grouping  into  units  larger  than  the  species  itself  seems 
impossible.  In  polycarpa  the  fruiting  bracts  and  seeds  are  much  reduced  in  size;  in 
hymenelytra  and  lentiformis  the  bracts  are  strongly  compressed;  in  confertifolia,  spinifera, 
and  parryi  there  appears  a  spiny  habit  in  addition  to  certain  peculiarities  in  the  bracts. 
The  most  divergent  species  is  A.  canescens,  in  which  the  fruiting  body  is  provided  with 
4  wing-like  outgrowths.  The  connections  between  these  species  will  be  further  discussed 
under  the  heading  of  relationships  as  each  is  reached  in  the  taxonomic  treatment.  Their 
diflferentia-ting  characters  are  illustrated  in  figure  43  (p.  314). 

CRITERIA  FOR  THE  RECOGNITION  OF  SPECIES  AND  SUBSPECIES. 
Seed. — The  most  nearly  constant  character  used  in  the  classification  of  the  species  of 
Atriplex  is  found  in  the  seed.  This  has  to  do  with  the  position  of  the  seed  within  the 
pericarp.  When  the  former  is  erect,  the  radicle  points  downwards,  thus  occupying  an 
inferior  or  basal  position  in  relation  to  the  plumule,  which  either  points  upwards  or  is 
curved  to  one  side.  In  a  few  species  {semibaccata,  californica,  and  others)  the  inferior 
radicle  is  turned  to  one  side  and  takes  up  a  lateral  position  beneath  the  tip  of  the  plumule. 
But  in  most  American  species  the  seed  is  inverted,  so  that  the  radicle  points  upwards. 
Such  radicles  are  said  to  be  superior  in  relation  to  the  plumule,  although  the  latter  also 
curves  upwards  and  its  tip  is  sometimes  as  high  as  that  of  the  radicle.  In  many  cases  the 
superior  radicle  curves  inward  at  tip  and  thus  comes  to  occupy  a  position  truly  superior 


CRITERIA.  241 

to  the  plumule.  These  various  positions  are  illustrated  in  the  plates  accompanying 
the  descriptions  of  the  species.  The  position  of  the  radicle,  whether  inferior  or  superior, 
is  utilized  in  the  assembling  of  the  species  into  two  subgenera,  Euatriplex  and  Obione,  as 
already  discussed. 

In  addition  to  the  vertical  seeds  just  described,  there  are  also  horizontal  seeds  in  one 
species,  namely  A.  hortensis.  In  this  species  the  vertical  seeds  are  borne  naked  between 
the  bracts,  whereas  the  horizontal  seeds  are  produced  only  in  those  flowers  in  which  a 
calyx  is  present.  According  to  Eichler  (Bluthendiagr.  2:84,  1875),  only  the  flowers  with 
horizontal  seeds  are  a  regular  part  of  the  inflorescence,  the  others  occurring  as  adventi- 
tious shoots.  Furthermore,  a  few  introduced  species  {patula,  rosea,  etc.)  produce  two 
kinds  of  vertical  seeds:  (1),  small  black  seeds  with  convex  sides,  the  tip  of  the  radicle 
scarcely  produced;  and  (2),  larger,  brownish  seeds  with  flat  sides  and  a  shallow  groove 
near  the  margin,  the  radicle  strongly  produced.  Only  the  latter  are  included  in  most 
descriptions.  Details  as  to  the  different  kinds  of  seeds  have  been  discussed  by  Collins 
(Seeds  of  Commercial  Saltbrushes,  U.  S.  Dept.  Agr.  Div.  Bot.  Bull.  27,  1901). 

Additional  seed  characters  doubtless  would  be  very  useful  in  the  classification  of  Atri- 
plexes,  if  consistently  applied.  The  paucity  of  mature  seeds  in  herbaria  precludes  the 
extensive  use  of  size  and  color  as  criteria  until  further  field  studies  and  collections  can  be 
made.  The  samples  preserved  in  seed  laboratories  are  not  very  helpful  in  this  connec- 
tion, since  they  are  but  rarely  accompanied  by  full  specimens  necessary  to  their  accurate 
identification.  It  is  believed  that  size  of  seed  will  prove  to  be  a  more  reliable  criterion 
than  size  of  fruiting  bracts,  since  the  latter  often  depends  largely  upon  the  extent  to 
which  such  purely  vegetative  structures  as  free  margins  and  appendages  are  developed. 
The  dimensions  and  color  of  the  seeds  as  described  in  the  present  paper  apply  to  these 
bodies  only  in  their  fully  mature  condition.  Much  confusion  would  result  from  measure- 
ments or  colors  determined  from  juvenile  material. 

Flowers. — The  flowers  of  Atriplex  are  of  two  sorts,  staminate  and  pistillate.  Thus  far 
the  former  have  been  scarcely  utilized  for  taxonomic  purposes,  except  as  to  their  arrange- 
ment, as  will  be  described  under  inflorescence.  The  depth  to  which  the  calyx  is  lobed  or 
cleft  is  much  greater  in  some  species  than  in  others,  but  there  is  also  much  variation  within 
single  species.  The  number  of  calyx-lobes  is  sometimes  given  in  descriptions,  but  it  is  of 
doubtful  value  and  never  to  be  depended  upon  as  a  criterion  unless  checked  by  the  exam- 
ination of  a  large  series  of  specimens.  Field  studies  indicate  that  the  staminate  flowers 
may  be  either  4-merous  or  5-merous  in  the  following  species:  patula,  rosea,  semibaccata, 
pusilla,  parishi,  truncata,  argentea,  coronata,  powelli,  leucophylla,  elegans,  and  lentiformis. 
The  variation  holds  even  within  single  subspecies  of  these,  and  in  most  of  them  it  has 
been  found  on  individual  plants.  On  the  other  hand,  only  5-merous  flowers  have  been 
found  on  bracteosa,  although  a  large  series  from  different  localities  was  examined.  Simi- 
larly, graciliflora  and  saccaria  yielded  only  5-merous  flowers,  but  only  a  limited  number 
of  plants  were  studied.  Usually  the  number  of  stamens  is  the  same  as  the  number  of 
calyx-lobes  in  the  same  flower.  Cases  of  5  stamens  accompanied  by  a  4-merous  caljoc 
have  been  found  in  truncata  and  leucophylla.  The  number  of  stamens  and  lobes  is  some- 
times reduced  to  3  each  in  elegans  and  probably  also  in  other  species.  Cases  of  a  double 
calyx,  that  is,  with  10  lobes,  are  not  rare.  The  original  number  of  calyx-lobes  and  sta- 
mens doubtless  was  5,  but  it  would  be  unsafe  to  assume  that  when  this  number  is  found  the 
species  in  hand  is  primitive.  This  would  lead  to  the  placing  of  species  like  bracteosa  at 
the  bottom  of  the  phylogenetic  tree,  while  by  all  other  criteria  they  are  classed  as  among 
the  most  highly  specialized  forms. 

Reference  has  thus  far  been  made  only  to  staminate  flowers.  The  pistillate  flower  is 
so  simple  as  to  yield  but  little  of  value  in  addition  to  the  pistil  itself,  which  has  been 
described  under  the  heading  of  seeds.     Obviously  the  perianth  is  a  mark  of  primitiveness 


242  GENUS   ATRIPLEX. 

when  it  occurs  in  pistillate  flowers.  It  has  been  found  only  in  hortensis,  dioeca,  monilifera, 
and  phyllostegia,  all  of  which  exhibit  other  features  of  a  primitive  nature.  In  phyllostegia 
the  perianth  may  be  either  present  or  absent,  even  in  flowers  of  the  same  plant,  and  vari- 
ous degrees  of  suppression  have  been  noted  (see  table  25,  p.  269). 

Fruiting  bracts. — These  structures  have  been  almost  universally  considered  as  modified 
upper  leaves.  Evidence  for  this  belief  was  given  by  Moquin-Tandon  (Chenop.  Enum. 
1840),  and  recently  the  case  has  been  stated  by  Collins  (U.  S.  Dept.  Agr.  Div.  Bot.  Bull. 
27:10,  1901).  After  reviewing  the  Australian  species,  Bentham  (Fl.  Austral.  5:166, 
1870)  came  to  the  conclusion  that  the  so-called  bracts  were  homologous  with  the  male 
perianth.  The  regular  occurrence  of  an  undoubted  perianth  between  the  bracts  and  the 
pistil  in  several  of  the  species  {hortensis,  dioeca,  phyllostegia,  the  first  the  type  of  the 
genus)  clearly  demonstrates  that  the  structures  under  consideration  are  true  bracts  and 
not  a  part  of  the  flower  proper.  This  view  was  later  adopted  by  Bentham  (in  Bentham 
and  Hooker,  Gen.  PI.  3:53,  1880). 

More  reliance  has  been  placed  upon  the  bract  characters  by  nearly  all  writers  on  the 
genus  than  upon  any  other  set  of  criteria,  and  very  much  more  than  their  value  warrants. 
The  bracts  vary  to  so  great  an  extent  that  the  extremes  seem  to  present  ideal  criteria  for 
the  recognition  of  species.  But  over  and  over  again  these  extremes  are  found  on  indi- 
vidual plants,  not  in  such  a  manner  as  to  indicate  hybridization,  but  rather  as  a  mark  of 
variation  between  the  individual  bracts.  Thus,  smooth  to  strongly  tuberculate  or  long- 
appendaged  bracts  very  frequently  are  found  on  single  plants  of  some  species,  as  also  are 
both  sessile  and  long-stalked  ones.  Examples  of  this  are  shown  in  some  of  the  illustra- 
tions (plates  41 ,  43,  44).  Many  more  are  mentioned  in  the  descriptions  of  the  species  and 
subspecies  and  under  the  minor  variations.  It  is,  of  course,  possible  that  such  qualities 
as  those  just  mentioned  are  heritable  and  that  the  mingling  of  different  types  of  bract 
on  the  same  plant  is  merely  the  outcome  of  a  heterozygous  condition.  If  this  is  the  case, 
then  the  utilization  of  such  features  for  purposes  of  classification  is  futile,  unless  all  of  the 
forms  are  first  subjected  to  a  close  genetical  analysis,  and  at  present  this  would  serve  no 
useful  purpose.  The  grouping  of  these  minor  variations  into  closely  defined  subspecies 
and  species  will  provide  a  classification  adequate  to  all  ordinary  needs.  An  alternate  ex- 
planation of  these  variations  is  that  they  are  ecologic  and  perhaps  correlated  with  the 
food-supply.  This  probably  is  the  case  when  variation  occurs  in  the  same  small  cluster  or 
between  the  bracts  of  a  single  pair,  as  often  happens.  In  Atriplex  parishi  it  has  been 
noted  that  in  some  plants  the  upper  bract  of  each  pair,  that  is  the  one  facing  the  stem,  is 
always  muricate,  whereas  the  bract  facing  downward  toward  the  subtending  leaf  is 
always  smooth.     The  significance  of  this  is  not  known. 

Although  the  sculpturing  of  the  bracts  and  the  length  of  their  stalks  are  characters  of 
but  little  value,  much  use  can  be  made  of  certain  other  features  connected  with  these 
structures.  Often  the  size  is  so  different  in  even  closely  related  species  that  this  may  be 
safely  employed  as  a  criterion.  Only  fully  mature  bracts  should  be  measured  for  this 
purpose.  The  size  character  would  be  more  definite  if  the  dimensions  of  the  body, 
exclusive  of  appendages,  wings,  or  free  margins  could  be  determined,  but  this  seems 
impracticable.  It  is  therefore  sometimes  necessary  to  make  allowance  for  unusual  sur- 
face outgrowths.  An  extreme  ca.se  of  variation  in  the  size  of  bracts  is  illustrated  in 
figure  31  (p.  252).  The  shape  is  also  helpful.  It  is  assumed  that  the  bracts  in  primitive 
forms  were  broadest  below  the  middle,  as  in  ordinary  foliage  leaves,  and  that  bracts 
broadest  near  or  above  the  middle  are  indicative  of  derived  groups.  United  bracts  are 
more  highly  specialized  than  distinct  ones,  since  these  structures  are  modifications  of 
distinct  leaves  of  the  inflorescence.  The  extent  of  fusion  is  helpful  in  working  out  phy- 
logenies,  but  it  is  difficult  to  express  in  the  form  of  a  proportion,  since  the  thin  margins, 
often  unequally  toothed,  should  first  be  eliminated.     Bracts  of  ordinary  leaf-like  texture 


CRITERIA.  243 

precede  both  exceptionally  hardened  and  unusually  fleshy  ones.  The  definitely  winged 
bracts  in  A.  canescens  are  the  result  of  a  development  quite  different  from  that  repre- 
sented by  irregular  appendages  and  indicate  a  divergent  phylogenetic  branch,  as  will  be 
further  noted  when  this  species  is  reached  in  the  taxonomic  sequence. 

Inflorescence. — All  stages  in  the  development  of  complete  dioecism  are  present  in 
Atriplex,  beginning  with  the  condition  in  which  the  sexes  are  mixed  in  small  axillary  clus- 
ters. As  the  two  kinds  of  flowers  began  to  separate,  the  staminate  came  to  occupy  the 
upper  axils,  the  pistillate  the  lower  ones.  The  staminate  inflorescence  is  sometimes 
very  long  and  branched  (bracteosa,  wrighti,  etc.),  sometimes  much  reduced  and  yet 
nearly  or  quite  pure  (fruticulosa,  leucophylla,  and  some  forms  of  pentandra).  Partial 
dioecism  has  been  attained  at  several  places  in  the  evolution  of  the  species  {phyllostegia, 
powelli),  but  it  becomes  complete  only  in  two  herbaceous  species  (decumbens,  matamor- 
ensis)  and  in  the  shrubs.  In  the  latter  group,  incomplete  dioecism  is  not  rare  in  several 
of  the  less  highly  evolved  forms  (barclayana,  nuttalli,  lentiformis) . 

The  size  of  the  staminate  inflorescence  and  its  degree  of  branching  are  useful  as  specific 
and  subspecific  criteria  in  only  a  few  cases.  At  other  times  there  is  considerable  varia- 
tion even  within  a  single  subspecies  {A.  pentandra  typica  and  A.  p.  muricata)  and  hybrids 
are  suspected  between  species  with  long  inflorescences  and  others  with  short  ones  {A. 
davidsoni,\>.  306). 

Leaves. — As  in  most  large  genera,  the  leaves  are  of  much  value  in  that  they  furnish 
corroborative  evidence  useful  in  the  identification  of  species,  but  not  to  be  relied  upon  in 
making  the  major  groupings.  They  are  usually  alternate,  but  in  a  few  species  {decum- 
bens, matamorensis)  they  are  mostly  opposite.  In  A.  parishi  the  position  varies  independ- 
ently of  other  characters.  It  has  been  determined  by  field  observation  and  verified  by 
garden  experiment  that  the  lower  leaves  in  most  and  probably  all  of  the  species  of  the 
argentea  and  pusilla  group  are  always  opposite.  Therefore  the  separation  of  species  in 
these  groups  on  the  basis  of  their  "alternate"  lower  leaves,  as  has  been  sometimes  done, 
is  not  warranted.  Such  errors  doubtless  are  the  result  of  the  incomplete  nature  of  many 
herbarium  specimens,  but  it  is  not  safe  to  assume  that  all  of  the  leaves  on  a  plant  were 
alternate  merely  because  the  remaining  ones  happen  to  be  so.  In  some  species  the  leaves 
are  closely  sessile,  in  others  decidedly  petioled.  The  chief  difficulty  in  using  this  feature 
lies  in  the  frequent  interposition  of  intermediate  species  or  minor  forms  in  which  the 
leaves  are  narrowed  below  to  a  petiole-like  base.  A  strong  tendency  is  noted  in  some  of 
the  more  primitive  herbaceous  species  to  the  formation  of  hastate  and  cordate  bases  to 
the  leaves,  and  this  recurs  in  a  few  of  the  shrubby  species.  All  gradations  from  a  strongly 
narrowed  to  a  broadly  hastate  base  are  found  in  A.  patula  and  nearly  all  stages  are  repre- 
sented also  in  A.  phyllostegia  and  A.  truncata.  The  amount  of  dentation  or  lobing,  the 
size,  the  shape,  and  the  texture  are  useful  in  some  cases  for  purposes  of  classification. 

Pubescence. — All  of  the  North  American  Atriplexes  are  glabrous,  except  for  a  more  or 
less  dense  scurf  consisting  of  modified  trichomes.  When  the  scurf  is  sparse  or  early  decid- 
uous, the  herbage  is  greenish  in  color.  This  condition  is  pronounced  only  in  the  subgenus 
Euatriplex  (especially  A.  hortensis  and  A.  patula),  in  the  more  primitive  species  of  sub- 
genus Obione  (notably  A.  dioeca  and  A.  phyllostegia)  and  in  A.  bracteosa.  The  remaining 
species  are  densely  scurfy,  at  least  on  the  lower  surface  of  the  leaves,  and  the  herbage  is 
therefore  gray  or  whitish  in  appearance.  This  diS'erence  in  color  is  an  aid  in  distinguish- 
ing on  sight  between  some  species  otherwise  much  alike  in  all  but  minute  technical  char- 
acters. However,  it  must  be  used  with  due  regard  to  the  presence  of  at  least  a  sparse 
scurfiness  on  the  juvenile  herbage  of  all  forms. 

Habit. — With  the  exception  of  the  anomalous  A.  calif ornica  and  the  two  introduced 
Australian  species,  all  of  the  subgenus  Euatriplex  and  all  of  Obione  up  to  the  pentandra 
group, as  diagrammed  in  the  chart  of  relationships  (p.  238), consists  of  herbaceous  annuals. 


244  GENUS   ATRIPLEX. 

The  transition  between  the  annual  and  the  perennial  habit  is  found  in  the  pentandra 
group,  where  the  change  takes  place  within  several  of  the  subspecies.  The  character  is 
here  useful  as  adding  to  the  characters  which  separate  the  annuals,  A.  bracteosa  and  A. 
wrighti,  from  the  similar  but  strictly  perennial  A.  linifoUa;  also  as  an  additional  criterion 
for  separating  the  annual  A.  microcarpa  from  the  perennial  A.  coulteri.  The  two  dioe- 
cious'herbs  following  this  group  are  perennials  with  a  somewhat  woody  base.  From 
here  on  to  the  end  of  the  genus  all  of  the  species  are  classed  as  shrubs,  although  some  of 
the  earlier  ones  are  only  subshrubs  with  herbaceous  branches.  The  distinction  between 
herbs  and  shrubs  is  here  more  useful  than  in  many  other  genera,  because  this  character 
runs  approximately  parallel  with  the  dioecious  habit. 

Other  features  of  the  habit,  such  as  the  method  of  branching,  direction  assumed  by  the 
stems  and  twigs,  size  of  plant,  and  degree  of  leafiness  are  of  some  assistance  in  distinguish- 
ing the  species  and  smaller  units,  but  fail  as  criteria  when  groups  of  species  are  involved. 

GENERIC  DIAGNOSIS. 
ATRIPLEX  Linnaeus,  Sp.  PI.  1052,  1753. 
Annual  and  perennial  herbs  and  shrubs,  more  or  less  pubescent  with  inflated  scurf-like 
hairs.  Leaves  alternate,  or  the  lower  opposite,  rarely  all  opposite,  sessile  or  petioled, 
entire  to  dentate  or  irregularly  and  deeply  lobed.  Flowers  monoecious  or  dioecious, 
solitary  or  in  glomerules,  the  single  or  clustered  flowers  in  the  leaf-axils  and  often  also  in 
terminal  spikes  or  panicles,  the  staminate  and  pistillate  flowers  often  mixing  in  the 
same  cluster,  but  the  staminate  usually  confined  to  the  upper  axils  or  to  terminal  inflores- 
cences. Staminate  flowers  without  bracts  or  bracteoles;  perianth  3-  to  5-parted,  the 
segments  obovate  or  oblong  and  obtuse;  stamens  3  to  5,  inserted  on  the  base  of  the  per- 
ianth, the  filaments  either  united  at  the  base  or  distinct,  the  anthers  2-celled;  rudiment  of 
the  ovary  conical  or  wanting.  Pistillate  flowers  each  subtended  by  2  bracts;  bracts 
accrescent,  distinct  or  usually  united  at  least  at  the  base  and  inclosing  the  fruit,  entire 
or  the  margins  variously  dentate,  sometimes  fleshy-thickened  or  spongious ;  perianth  none 
or  rarely  present  and  then  consisting  of  a  3-  to  5-lobed  membranous  calyx  or  of  1  to  5 
squamellae;  disk  and  rudimentary  stamens  wanting;  ovary  ovoid  or  depressed-globose; 
stigmas  2,  nearly  filiform,  or  slightly  thickened  or  compressed  near  the  base,  where  also 
shortly  connate;  ovule  oblique  or  erect  and  with  a  short  funicle,  or  inverted  and  suspended 
from  the  end  of  an  elongated  funicle.  Utricle  inclosed  between  the  bracts,  the  pericarp 
membranaceous  and  usually  free  from  the  seed.  Seed  erect  or  inverted,  rarely  hori- 
zontal, the  coats  membranaceous,  coriaceous  or  almost  crustaceous;  embryo  annular, 
surrounding  the  farinaceous  albumen,  the  radicle  inferior,  lateral,  or  superior. 

Artifieial  Key  to  the  Species  of  Atriplex.^ 

Plant  an  herb,  sometimes  slightly  woody  at  base,  but  not  shrubby. 

Foliage  green  or  greenish  on  both  surfaces,  sparsely  mealy  and  therefore  some- 
times grayish  when  young. 
Bracts  orbicular  or  rounded-ovate,  10  mm.  or  more  broad. 

Staminate  flowers  mixed  with  the  pistillate;  leaf-blades  4  to  12  cm.  long I.  A.  hortensis  (p.  247). 

Staminate  flowers  in  terminal  panicles,  the  pistillate  in  the  leaf-axils;  leaf- 
blades  1  to  2  cm.  long 19.  A.  graeiliftora  (p.  279). 

Bracts  not  orbicular,  less  than  5  mm.  broad. 
Fruiting  bracts  united  only  near  the  base;  staminate  flowers  mixed  with  the 
pistillate  or  in  very  short  spikes. 
Bracts  hastate  to  rounded  or  cuneate  at  base;  radicle  pointing  downwards.  .     2.  A.  patula  (p.  248). 
Bracts  mostly  with  rounded  ear-like  lobes  near  the  base;  radicle  pointing 

upwards.     (Interior  species.) 11.  A.  phylloategia  (p.  266). 

Fruiting  bracts  united  to  above  the  middle;  staminate  flowers  mostly  in  glom- 
erules of  elongated  terminal  spikes  or  panicles. 
Leaves  strictly  entire;  calyx-lobes  crested  on  the  back.     Rocky  Mountains 

to  Nebraska  and  northward 9.  A.  dioeca  (p.  264). 

Leaves  mostly  sharp-toothed;  calyx-lobes  smooth.     Nevada  and  Cahfornia. .  29.  A.  bracteosa  (p.  305). 

■  A  natural  grouping  of  the  species  is  given  in  a  series  of  phylogenetic  charts  to  be  found  on  pages  238,  270,  278,  293, 
and  314. 


KEY  TO  SPECIES. 


245 


Artificial  Key  to  the  Species  of  ^irtplex— Continued. 
Foliage  gray  or  whitish,  with  a  fine  scurf,  at  least  on  the  lower  surface. 

Introduced  perennials;  bracts  thickened,  either  fleshy  and  turning  red  or  spongy.  ■■        ,    ,     oco\ 

Bracts  fleshv,  stronglv  nerved,  ovate 7.  ^.  semiftaccafa  (p.  2bi). 

Bracts  spongy,  drv,  fibrous,  turbinate  or  apparently  globoid 8.  A.  halimoides  (p.  iM). 

Native  annuals" and  perennials;  bracts  neither  fleshy-thickened  nor  spongy. 
Fruiting  bracts  broadest  below  the  middle. 
Staminate  glomerules  in  long  naked  terminal  spikes. 
Leaves  alternate. 

Staminate  and  pistillate  flowers  on  separate  plants;  plant  woody  at 

base 38.  A.  nuttalh  (p.  322). 

Staminate  and  pistillate  flowers  on  the  same  plant;  plant  an  herbaceous 

annual 10.  A.  mondifera  (p.  265). 

Leaves  mostly  opposite.     A  Pacific  Coast  perennial  with  staminate  and 

pistillate  flowers  on  separate  plants 33.  A.  decuTnbens  (p.  311). 

Staminate  glomerules  in  the  upper  leaf-axils  or  in  spikes  1  cm.  or  less  long. 
Leaves  coarsely  toothed;  bracts  becoming  hard  and  indurated  (see  also 

A.  tatarica  and  A.  maritima) 5.  A.  rosea  (p.  259). 

Leaves  entire;  bracts  not  becoming  hard.  „     .       ,r      ■      ,     oc-i, 

Plant  prostrate;  root  perennial,  fusiform;  bracts  distinct  to  the  base. ...     3.  A.  ealifornica  (p.  Zb/). 
Plant  erect  or  spreading;  root  annual,  slender;  bracts  united  to  the 
middle  or  above. 
Stem  simple  or  with  a  few  virgate  branches,  the  plant  usually  2  to  10 

dm.  high;  fruiting  bracts  2.5  to  5  mm.  long.  .,       ,     n^rv\ 

Leaves  cordate  at  base;  bracts  4  to  5  mm.  long 12.  A.  cordidata  (p.  269). 

Leaves  rounded  at  base;  bracts  2.5  to  3.5  mm.  long 13.  A.  tularensts  (p.  271). 

Stem  intricately  branched  throughout,  the  whole  plant  rounded,  often 
depressed,  usually  0.5  to  3  dm.  high;  fruiting  bracts 

1  to  3.5  mm.  long. 

Fruiting  bracts  1  to  1.5  mm.  long,  very  smooth,  pungently  acute.  .    14.  A.  pusiUa  (p.  272). 
Fruiting  bracts  2  to  3.5  mm.  long,  at  least  some  of  them  tubercu- 
late  or  appendaged,  obtuse  to  merely  acute  at  apex. 
Branches  ascending,  slender,  not  especiallv  brittle;  fruiting  bracts  .    .       ,     o-on 

2  to  3  mm.  long.     Rocky  Mountains 15.  A.  tenuisnma  (p.  273). 

Branches  widelv  spreading,  often  horizontal  and  the  lower  ones 

decumbent,  brittle,  breaking  into  joints  when  dry; 

fruiting  bracts  2.5  to  3.5  mm.  long.     California 16.  A.  panshi  (p.  274). 

Fruiting  bracts  broadest  at  or  above  the  middle. 

Leaves  cordate  at  base  or  the  bracts  euneate  in  shape  and  truncate  at  summit. 
(All  strictly  annuals.     A.  eorrugata  and  A.  nuttalU, 
both  dioecious  subshrubs,  might  be  sought  here.) 
Base  of  leaf  not  cordate.  . 

Leaves  deltoid  to  elliptic,  0.8  to  2  cm.  wide;  bracts  2  to  3  mm.  long 17.  A.  truncata  (p.  27b;. 

Leaves  linear,  0.2  cm.  or  less  wide;  bracts  1.5  to  2  mm.  long 18.  A.  wolfi  (p.  279). 

Base  of  leaf  cordate.  ,„     .  .,  -       /     o■7n^ 

Bracts  orbicular  to  oblong,  with  broad  flat  margins 19.  A.  graciliflora  (P- 2/9;. 

Bracts  globoid  or  euneate,  not  margined  but  mostly  long-appendaged .  .   20.  A.  saccana  (p.  280). 
Leaves  not  cordate  at  base  and  the  bracts  not  euneate  and  with  truncate 
summit. 
Bracts  becoming  hard  and  almost  bone-like;  radicle  pointing  downwards 
or  to  one  side  in  the  embryo.     Introduced  weeds. 
Terminal  staminate  inflorescences  1  cm.  or  less  long;  leaves  sinuate  or 
repand-dentate,  usually  gray  on  both  surfaces. 

Plant  spreading  or  prostrate;  bracts  6  to"9  mm.  long 4.  A.  marilima  (p.  258). 

Plant  erect;  bracts  4  to  6  or  rarely  8  mm.  long 5.  A.  rosea  (p.  259). 

Terminal  staminate  inflorescences  3  to  15  cm.  long;  leaves  deeply  lobed 

or  subpinnatifid,  greenish  above • 6.  A.  tatarica  (p.  261). 

Bracts  not  becoming  especially  hard;  radicle  pointing  upwards  in  the 
embryo.     Native  species. 
Staminate  and  pistillate  flowers  mostly  mixing  in  the  clusters. 
Bracts  irregularly  toothed  at  summit,  without  wing-hke  crown. 

Leaves  ovate  to   deltoid,   broad  and  often   subhastate  at  base, 

mostly  1  to  4  cm.  wide;  bracts  4  to  8  mm.  long 21.  A.  argentea  (p.  iHi). 

Leaves  narrowly  ovate  to  mostly  elliptic,  narrowed  at  the  base,  0.3 

to  1  cm.  wide;  bracts  3  to  4  or  rarely  5  mm.  long.  .   22.  A.  coronata  (p.  288). 

Bracts  crowned  with  a  broad  smooth  wing-hke  appendage 23.  A.  powelli  (p.  290). 

Bracts  flat,  exactly  orbicular,  evenly  toothed  all  around 26.  A.  elegans  (p.  300). 

Staminate  and  pistillate  flowers  mostly  in  separate  clusters,  the  stami- 
nate terminal  or  on  separate  plants. 
Leaves  strongly  3-nerved  from  the  base,  ovate;  bracts  crowned  by  a 

horizontal  wing-like  lobe 23.  A.  powelli  (p.  290). 

Leaves  1-nerved  or  the  nerve  obscure. 

Pistillate  and  staminate  flowers  on  the  same  plant;  leaves  chiefly 
alternate. 
Bracts  not  compressed,  elliptic-globose,  5  to  7  mm.  long;  seed 

2.5  to  3  mm.  long.     Perennial  of  the  CaUfornian  ,   „    ,     „„„x 

coast 24.  A.  UucophyUa  (p.  292). 


246  GENUS   ATRIPLEX. 

Artificial  Key  to  the  Species  of  A  triplex — Continued. 
Bracts  more  or  less  compressed  except  when  under  4  mm.  long; 
seed  1.5  mm.  or  less  long. 
Fruiting  bracts  exactly  orbicular,  toothed  all  around.     Desert 

annual 26.  A.  elegant  (p.  300). 

Fruiting  bracts  cuneate-orbicular  to  obovate,  entire  near  the 
base. 
Inflorescence  of  staminate  glomerules  5  to  30  cm.  long. 
Plant  annual;  leaves  mostly  dentate. 
Leaves  broadest  above  the  middle,  lower  surface  white.  28.  A.  wrighli  (p.  304). 
Leaves  broadest  below  the  middle,  lower  surface  greenish.  29.  A.  bracteosa  (p.  305). 

Plant  perennial;  leaves  all  entire 30.  A.  linifolia  (p.  308). 

Inflorescence  of  staminate  glomerules  3  cm.  or  less  long,  or 
flowers  all  axillary. 
Length  of  fruiting  bracts  1  to  2  mm.     Pacific  Coast  annual 

with  entire  leaves 27.  A.  mierocarpa  (p.  303). 

Length  of  fruiting  bracts  2.5  mm.  or  more. 

Fruiting   bracts  globoid,  not  compressed.     CaUfornian 

perennial 31.  A.  frutieruloaa  (p.  309). 

Fruiting  bracts  obovate,  compressed  but  sometimes 
thickened  by  numerous  appendages.  Forms  of  the 
Californian  A.  bracteosa  with  reduced  staminate 
inflorescences  might  be  sought  here,  but  distin- 
guished by  its  evil  odor  and  from  No.  32  by  the 
dentate  leaves. 
Branches  erect  or  spreading  but  always  with  erect  or 
ascending  ends,  thickish,  from  an  annual  or  her- 
baceous-perennial base;  leaves  entire  or  toothed, 
commonly  larger  than  in  the  next,  often  obtuse. 
Mexico  and  Texas  to  the  West  Indies  and  New 

England 25.  A.  pentandra  (p.  294) 

Branches  mostly  prostrate  at  least  at  first,  slender, 
from  a  short  woody  perennial  base;  leaves  all  entire, 
1  to  2  cm.  long,  0.2  to  0.4  cm.  wide,  acute.  Cali- 
fornian coast 32.  A.  coulteri  (p.  310). 

Pistillate  and  staminate  flowers  on  separate  plants;  leaves  chiefly 

opposite 34.  A.  matamorensis  (p.  312) . 

(Here  might  be  sought  also  nuttalli,  corrugata,  obo- 
vata,  and  acanthocarpa,  all  dioecious  subshrubs  with 
alternate  leaves.     See  under  next  heading.) 
Plant  a  shrub  or  subshrub. 
Bracts  never  with  4  conspicuous  longitudinal  wings.     (Irregular  flattened  appen- 
dages are  not  to  be  mistaken  for  wings.) 
Plant  not  spiny. 

Mature  bracts  4  to  8  mm.  or  more  long,  either  narrower  or  broader  than  long. 
Margin  of  leaf  entire  or  only  undulate. 
Leaves  narrowed  at  base,  0.5  to  3.5  cm.  long,  or  longer. 

Tall  shrubs,  10  to  30  dm.  high;  bracts  orbicular 43.  A.  lentiformis  (p.  334). 

Low  shrubs,  1  to  10  dm.  high;  bracts  never  exactly  orbicular. 
Bracts  longer  than  broad. 

Bracts  lanceolate  to  elliptic  or  cuneate-oblong,  entire  or  toothed  at 

summit 38.  A.  nuttalli  (p.  322). 

Bracts  narrowly  fan-shaped,  ending  above  in  a  broad  free  transverse 

lobe 39.  A.  corrugata  (p.  330). 

Bracts  broader  than  long 37.  A.  obovata  (p.  321). 

Leaves  sagittate-clasping,  0.2  to  0.4  cm.  long 41.  A.  julacea  (p.  333). 

Margin  of  leaf  dentate. 

Bracts  globoid,  not  compressed 36.  A.  acanthocarpa  (p.  320) 

Bracts  orbicular,  strongly  compressed 42.  A.  hymenelytra  (p.  333). 

Mature  bracts  2  to  4  mm.  long,  about  as  broad  as  long  or  broader. 
Leaves  medium-sized  or  large,  0.5  to  5  cm.  wide,  1  to  5  cm.  long. 

Stems  herbaceous  above;  bracts  not  truly  orbicular.     Mexican 35.  A.  barclayana  (p.  313). 

Stems  woody  throughout;  bracts  orbicular 43.  A.  lentiformis  (p.  334). 

Leaves  small,  0.2  to  0.4  cm.  wide,  0.3  to  1.5  cm  long  (longer  only  on  sterile 

shoots) 40.  A.  polycarpa  (p.  331). 

Plant  spiny,  the  spines  consisting  of  slender  rigid  sharp-pointed  twigs  from  which 
the  leaves  or  fruiting  bracts  have  fallen. 
Bracts  orbicular,  or  broader  than  long  in  one  form  with  wing-angled  twigs.  ...   43.  A.  lentiformis  (p.  334). 
Bracts  not  orbicular;  the  twigs  terete  or  obtusely  angled. 
Leaves  not  cordate  at  base;  bracts  6  to  15  mm.  long. 

Body  of  bract  small,  not  contracted  beneath  the  free  terminal  wings; 

leaves  strictly  entire 44.  A.  confertifolia  (p.  338). 

Body  of  bract  large,  thick,  contracted  to  a  neck  beneath  the  free  terminal 

wings;  some  of  the  leaves  subhastat*  at  base 45.  A.  spinifera  (p.  340). 

Leaves  cordate  at  base;  bracts  3  to  4  mm.  long 46.  A.  parryi  (p.  341). 

Bracts  with  4  conspicuous  longitudinal  wings  extending  the  whole  length  of  the 

body  and  often  beyond 47.  A.  canescens  (p.  342). 


A.    HORTENSIS.  247 

1.  ATRIPLEX  HORTENSIS  Linnaeus,  Sp.  PI.  1053,  1753.    Plate  36.    Gardenscale; 
Gabden  Orache. 

Mostly  erect  but  often  half-decumbent  coarse  annual  herb,  5  to  20  dm.  high,  widely 
branched  from  the  base,  the  upper  twigs  ascending;  branches  slender  or  stout,  strongly 
angled,  lightly  furfuraceous  when  young  but  soon  glabrous  and  green,  the  old  bark  white ; 
leaves  alternate  except  the  lower,  petioled,  ovate  varying  to  somewhat  triangular  and 
to  lance-oblong,  truncate,  cordate  or  subhastate  at  base,  or  the  upper  slightly  rounded 
to  the  petiole,  obtuse  at  apex,  4  to  12  or  rarely  20  cm.  long,  3.5  to  9  cm.  wide,  the  margins 
entire  to  sinuate-dentate,  rather  thin,  farinose  when  young,  bright-green  and  usually 
glabrous  in  age  (all  densely  whitish  furfuraceous  beneath  in  minor  variation  5,  A.  sagit- 
tata  Borkhausen);  flowers  monoecious,  spicate  along  the  branches  of  an  elongated  ter- 
minal panicle,  the  staminate  and  pistillate  flowers  somewhat  mixed  in  the  inflorescence 
but  the  former  often  also  in  pure  terminal  spikes;  perianth  3-  to  5-lobed,  wanting  in  most 
of  the  pistillate  flowers  (the  fruit  then  vertical,  but  horizontal  when  the  perianth  is  pres- 
ent); fruiting  bracts  short-pedicellate,  strongly  compressed,  united  only  at  the  base, 
nearly  orbicular  or  rounded-ovate,  always  slightly  narrowed  above,  becoming  char- 
taceous,  8  to  18  mm.  long,  nearly  as  wide,  the  broad,  thin  margins  entire  or  obscurely 
denticulate,  the  faces  smooth  but  strongly  reticulate- veiny;  seed  2  to  4  mm.  long  and 
brown,  or  only  1.5  mm.  long  and  black  when  horizontal;  radicle  inferior. 

Apparently  of  garden  origin,  but  perhaps  native  in  central  Asia  (see  further  under 
Relationships),  introduced  in  many  widely  separated  parts  of  the  United  States  and 
Cuba.  Type  locality,  Siberia.  Collections:  South  Boston,  Massachusetts,  1878,  Faxon 
(Or);  ballast  grounds,  Gowans,  Long  Island,  New  York,  September  17,  1879,  Brown 
(NY,  form  is  A.  sagittata  Borkhausen);  Jersey  City,  New  Jersey,  1878,  Brown  (NY,  same 
form) ;  Santiago  de  las  Vegas,  Cuba,  van  Hermann  7S9  (NY) ;  Naperville,  Illinois,  August 
3,  1895,  Umbach  (US);  Benson  County,  North  Dakota,  August  4,  1890,  Lunnell  (US); 
Bozeman,  Montana,  September  5,  1901,  W.  W.  Jones  (Gr,  UC,  US);  Boulder,  Colorado, 
Osterhout  ^421  (NY);  Ephraim,  Utah,  Tidestrom  548  (US);  Salmon,  eastern  Idaho,  Hall 
11654  (UC);  Ontario,  southeastern  Oregon,  Griffiths  913  (NY,  US). 

MINOR  VARIATIONS  AND  SYNONYMS. 

A  considerable  number  of  forms  have  been  described  in  Europe  and  Asia,  mostly  as  varieties.  Only  the 
following  seem  to  apply  to  American  plants.  The  color,  used  to  distinguish  some  of  these,  appears  to  be  a 
fluctuating  character  as  far  as  American  plants  are  concerned,  but  in  Europe  some  color  forms  apparently  are 
fixed  (according  to  Miller,  Card.  Diet.,  ed.  8,  1768,  as  quoted  by  Moss,  Cambr.  Brit.  Fl.  2: 169,  1914).  Perhaps 
these  permanent  races  have  not  been  introduced  into  this  country. 

1.  A.  HORTENSIS  MicROSPBRMA  MoquiH,  Cheuop.  Enum.  52,  1840,  consists  of  plants  with  small  fruits,  the 
bracts  and  leaves  green. 

2.  A.  HORTENSIS  OBTUSiFOLiA  Moquin,  in  DeCandoIle,  Prodr.  13':  91,  1849,  is  the  common  green  form,  with 
very  obtuse  leaves  and  large  bracts. 

3.  A.  HORTENSIS  RUBRA  Linnacus,  Sp.  PI.  1053,  1753,  has  leaves  and  bracts  becoming  reddish.  Specimens 
from  Golden,  Colorado,  and  especially  the  collection  from  Idaho  cited  above,  have  reddish  bracts,  and  other 
American  collections  exhibit  tendencies  in  this  direction. 

4.  A.  NiTENS  Schkuhr,  Handb.  3:541,  1803.— This  is  the  name  usually  applied  to  the  earlier  A.  sagMata 
Borkhausen  (No.  5  of  this  list).  The  taxonomic  equivalence  is  indicated  by  Schkuhr's  citation  of  sagiltala  as 
a  synonym.  Schkuhr  also  cites  an  A.  vdridis  Ehrhart,  but  this  doubtless  refers  to  Ehrhart's  erroneous  identifi- 
cation of  the  plant  with  A.  viridis  Crantz,  that  is,  Chenopodium  album  Linnaeus. 

5.  A.  SAGITTATA  Borkhausen,  Rhein.  Mag.  477,  1793. — The  oldest  name  for  the  form  which  commonly  passes 
in  Europe  as  A.  nitens.  It  has  been  sparingly  introduced  into  America,  as  indicated  among  the  above  citations. 
The  characters  differ  from  those  of  horlensis  only  in  the  more  shining  upper  surface  of  the  leaves  and  a  rather 
persistent  furfuraceous  coating  on  the  under  surface.  Borkhausen  described  the  leaves  as  shining  green  above 
and  bluish-green  beneath.  He  also  indicated  some  leaf  and  habit  characters  which  are  now  well  known  to  be 
much  too  variable  for  use.  The  size  of  the  seed  has  been  used  by  others  to  distinguish  between  hortemis  and 
iogilUita,  the  seed  of  the  former  being  given  as  about  2  mm.  long,  and  of  the  latter  as  3  to  3.5  mm.,  but  seeds  of 
undoubted  hortensis  from  France  are  as  much  as  4  mm.  long  (borders  of  fields  in  the  Maures,  September  23, 
1869,  Huet,  Gr.  Hb.).  If  retained  as  a  subspecies  or  variety,  the  name  nitens  is  suggested  as  the  more  distinctive 
and  at  the  same  time  more  in  accordance  with  usage  when  this  variant  is  treated  as  a  species. 


248  GENUS  ATRIPLEX. 

RELATIONSHIPS. 

The  principal  characters  of  this  species  indicate  that  it  is  close  to  the  primitive  type 
of  Atriplex.  The  retention  of  the  perianth  in  about  25  per  cent  of  the  pistillate  flowers, 
the  inferior  radicle,  and  the  herbaceous  and  monoecious  habit  all  indicate  an  absence  of 
specialized  development,  which,  however,  is  noted  in  some  minor  details.  It  has  no 
close  relatives  in  America,  where  it  is  known  only  as  an  introduced  plant.  It  has  been 
suggested  by  Beck  (Icon.  24:128,  1908)  that  it  has  originated  in  cultivation,  and  Moss 
(Cambr.  Brit.  Fl.  2:170,  1914)  admits  this  as  a  possibility.  However,  these  authors 
refer  to  the  species  exclusive  of  A.  nitens  (see  4  and  5  of  the  minor  variations),  and  when 
so  restricted  A.  hortensis  is  not  positively  known  anywhere  as  a  native  plant.  It  seems 
quite  probable  that  A.  nitens,  which  is  a  native  of  Central  Asia  and  especially  of  Tibet,  is 
the  original  form  and  that  the  common  hortensis  has  bee'n  derived  as  a  consequence  of  the 
suppression  of  scurf  on  the  under  surface  of  the  leaves.  If  this  assumption  is  correct, 
the  ancestral  home  of  the  genus  probably  was  in  central  Asia.  Furthermore,  the  true 
or  phylogenetic  type  of  the  species  is  A.  nitens,  while  the  nomenclatorial  type  remains  as 
the  earlier  A.  hortensis.  Throughout  this  discussion  the  well-established  name  of 
nitens  has  been  used  for  a  form  which  should  be  designated  as  A.  sagittata  if  the  rules  of 
nomenclature  are  strictly  followed  (see  Nos.  4  and  5  of  the  minor  variations). 
ECOLOGY  AND  USES. 

Atriplex  hortensis  is  an  annual  herb,  which  has  escaped  from  gardens  to  become  a  weed 
in  waste  places,  and  especially  along  ditches  and  in  depressions.  As  a  temporary  weed 
of  infrequent  occurrence  it  plays  little  part  in  vegetation,  and  its  ecological  behavior  is 
negligible.  The  plants  bloom  from  spring  to  late  summer,  and  the  showy  colored  fruits 
persist  through  the  autumn. 

Orache,  as  this  species  is  commonly  known,  is  much  grown  in  Europe  and  also  to  a 
limited  extent  in  America  as  a  food  plant.  It  is  often  called  French  spinach,  this  name 
indicating  the  use  to  which  it  is  put.  There  are  numerous  garden  varieties,  differing 
from  one  another  in  habit,  taste,  and  especially  in  color.  Some  have  dark-red  herbage 
and  fruiting  bracts,  but  the  color  disappears  on  cooking.  A  variety  with  white  stems  and 
pale  foliage  is  said  to  be  the  one  most  commonly  grown.  A  crimson-leaved  variety  {atro- 
sanguinea  of  the  gardeners)  is  a  favorite  for  ornamental  purposes.  These  various  color 
forms  come  true  to  seed  in  garden  cultures.  One  authority  states,  after  40  years  of  obser- 
vation, that  he  has  never  seen  them  to  vary  (Miller,  Gard.  Diet.,  ed.  8,  1768).  Although 
the  gardenscale  frequently  escapes  in  America  and  then  becomes  a  weed,  it  will  never 
cause  much  trouble.  It  grows  only  in  moist,  waste  places  and  soon  disappears  when  cul- 
tivation is  practiced. 

2.  ATRIPLEX  PATULA  Linnaeus,  Sp.  PL  1053, 1753.    Plate  37.    Spearscale; 
Speak  Orache. 

Erect,  decumbent,  or  prostrate  annual  herb,  varying  greatly  in  habit  and  size,  usually 
2  to  10  dm.  high,  but  sometimes  reduced  to  less  than  1  dm.  in  simple-stemmed  plants, 
sometimes  up  to  15  dm.  when  growing  in  thickets,  simple  to  widely  branched;  branches 
slender  or  stout,  rather  rigid,  smooth  in  small  and  young  plants,  but  commonly  grooved 
or  with  numerous  vertical  ribs,  these  white  or  pale,  the  intervals  green;  leaves  perhaps 
always  opposite  below,  usually  alternate  above,  but  sometimes  all  opposite,  petioled  or 
sometimes  sessile,  typically  subdeltoid-lanceolate  or  ovate,  but  varying  from  broadly 
triangular-hastate  to  linear,  attenuate  to  cordate  or  hastate  at  base,  acute  or  obtuse  at 
apex,  exceedingly  variable  as  to  size,  the  margins  entire  or  coarsely  dentate,  somewhat 
fleshy,  sparsely  or  densely  furfuraceous  when  young,  usually  glabrate  and  green  at 
maturity;  flowers  monoecious,  in  glomerules  the  lower  of  which  are  sometimes  in  the 
leaf-axils,  the  upper  glomerules  commonly  in  simple  or  compound  spikes,  the  staminate 


A.    PATULA. 


249 


and  pistillate  usually  in  the  same  small  clusters;  perianth  4-  or  5-cleft,  wanting  in  all  of 
the  pistillate  flowers;  fruiting  bracts  sessile  or  stalked,  not  much  compressed,  sometimes 
thickened  and  spongious  (especially  in  subspecies  alaskensis),  united  only  near  the  base, 
broadly  deltoid  to  linear,  3  to  12  mm.  long,  about  as  wide,  herbaceous,  becoming  slightly 
hardened  in  only  one  variant  (subspecies  glahriuscula) ,  the  broad  free  margins  entire  or 
sparsely  denticulate,  the  faces  smooth  or  muricate  or  with  clustered  tubercles,  often 
with  prominent  veins;  seed  1  to  3  or  rarely  4  mm.  long,  dark  brown  or  black;  radicle 
inferior. 

In  saline  soil  and  in  salt  marshes  throughout  North  America,  except  possibly  in  north- 
central  Canada  and  southern  Mexico;  also  in  Europe,  Asia,  and  northern  Africa. 

SUBSPECIES. 
The  variable  characters  in  A.  patula  are  so  numerous  that  it  is  difficult  to  make  a 
selection  of  those  that  lead  to  the  assembling  of  the  most  closely  related  variations  into 
natural  subspecies.  It  is  believed,  however,  that  a  primary  division  based  upon  the 
width  and  dentation  of  the  margins  of  the  fruiting  bracts  is  the  most  reliable.  While 
this  feature  is  generally  applicable,  warning  should  be  given  that  the  teeth  are  some- 
times so  minute  as  to  be  easily  overlooked,  and  occasionally  the  assemblage  of  other 
features  indicates  that  a  plant  with  entire  bracts  belongs  to  a  subspecies  with  usually 
dentate  bracts,  and  vice  versa.  There  seems  to  be  no  method  of  escaping  this  condition 
in  a  species  so  given  to  individual  variation.  Shape  of  leaf,  and  its  corresponding 
expression  in  the  modified  leaves  called  bracts,  is  a  useful  secondary  character.  Any 
considerable  increase  in  the  number  of  recognized  subspecies  doubtless  would  lead  to  a 
confusion  comparable  to  that  obtaining  in  the  European  literature  on  the  species,  since 
it  would  necessitate  the  use  of  single-character  criteria.  The  most  notable  minor 
variation,  and  one  which  perhaps  will  require  subspecific  rank  when  the  constancy  of 
its  characters  are  better  known,  is  A.  carnosa  Nelson,  which  may  be  synonymous  with 
the  earlier  names,  Chenopodium  subspicatum  Nuttall  and  Atriplex  lapathifolia  Rydberg. 

Key  to  the  Subspecies  oj  Atriplex  patiUa. 
Bncts  with  narrow  toothed  margins,  the  teeth  sometimes  very  small  and  sparse. 

Leaf-blades  in  part  triangular-hastate  or  rhomboidal,  with  basal  angles  or  lobes; 
bracts  truncate  or  broadly  rounded  at  base. 

Inflorescence  not  leafy,  spicate-paniculate;  leaves  mostly  large (a)  hastata  (p.  249). 

Inflorescence  leafy,  each  glomerule  in  axil  of  a  well-developed  leaf;  leaves  small. .    (b)  glahriuscula  (p.  250). 
Leaf-blades  lanceolate  or  oblong  to  linear,  not  hastate;  bracts  more  often  narrowly 
rounded  or  broadly  cuneate  at  base. 

Blades  lanceolate  or  oblong;  bracts  usually  smooth  on  the  face (c)  lypica  (p.  251). 

Blades  linear;  bracts  tubercled  on  the  face (d)  litoralis  (p.  251). 

Bracts  with  wider  entire  margins. 

Bracts  small,  about  3  mm.  long;  leaves  ovate-rhombic,  coarsely  toothed («)  spicaia  (p.  251). 

Bracts  larger,  4  to  12  or  even  20  mm.  long;  leaves  narrower,  entire  or  shallowly  toothed. 
Base  of  bract  not  especially  thickened  nor  spongious. 

Bracts  ovate  or  rhomboidal;  leaves  mostly  lance-oblong  or  the  upper  ones 

hnear (/)   obtusa  (p.  252). 

Bracts  hnear;  leaves  Unear (?)  zosteraefoha  (p.  252). 

Base  of  bract  much  thickened,  spongious i.h)  alaskensis  (p.  253). 

2a.  Atriplex  patula  hastata  (Linnaeus). — Plant  usually  erect  and  the  branches  as- 
cending, but  the  lower  ones  sometimes  decumbent,  strict  and  with  few  short  branches 
in  dwarf  forms,  widely  branched  and  up  to  15  dm.  high  in  luxuriant  forms  of  better 
soil  or  where  protected;  leaves  large,  petioled;  blade  deltoid  or  triangular,  commonly 
hastate  at  base,  sinuate-dentate  to  entire,  rarely  laciniate-dentate  (thick,  firm,  and 
less  obviously  hastate  in  minor  variation  3,  A.  carnosa  Nelson);  glomerules  scattered 
along  the  spike-like  branches  of  a  terminal  panicle  (densely  spicate  and  persistent  in 
minor  variation  3) ;  fruiting  bracts  ovate  or  triangular,  3  to  7  mm.  long,  broadly  rounded 
or  truncate  at  base,  the  margins  usually  with  a  few  tooth-like  projections,  rarely  more 
deeply  dentate,  the  face  commonly  tuberculate.     {A.  hastata  Linnaeus,  Sp.  PL,  1053, 


250  GENUS   ATRIPLEX. 

1753.)  Abundant  in  suitable  places  throughout  the  United  States,  except  in  the  ex- 
treme southeast,  north  to  Newfoundland,  Saskatchewan,  and  British  Columbia;  also 
a  common  subspecies  in  the  Old  World.  Type  locality,  Europe.  Collections:  Valley 
of  Exploits  River,  Newfoundland,  Fernald  and  Wiegand  5368  (Gr);  New  Brunswick, 
J.  D.  Smith  843  (US);  Canso,  Nova  Scotia,  August  10,  1901,  Foxvler  (US);  Gaspe  County, 
Quebec,  Collins,  Fernald,  and  Pease  (Gr);  Milton,  Ontario,  October  12,  1900,  Moore 
(UC);  sea-beach  of  Massachusetts,  True  87a  (US);  District  of  Columbia,  Canby  (US); 
Hyde  County,  North  Carolina,  Kearney  2282  (US);  Port  Eads,  Louisiana,  on  ballast, 
May  6,  1885,  Langlois  (US);  Missouri,  Nuttall  (Gr,  type  collection  of  Chenopodium  sub- 
spicatum  Nuttall,  minor  variation  24);  Iowa  City,  Iowa,  Somes  3645  (US);  Pen  Yan, 
New  York,  Wright  (US);  Denver,  Colorado,  Eastwood  143  (Gr,  UC,  minor  variation  3, 
A.  carnosa  Nelson);  Laramie,  Wyoming,  Nelson  8086  (R,  NY,  US,  type  collection  of 
A.  carnosa  Nelson,  minor  variation  3);  Colgate,  Montana,  Sandberg  1018  (Gr,  same 
variation);  New  Plymouth,  Idaho,  Macbride  725  (DS,  UC,  same  variation);  St.  George, 
Utah,  Jones  6098  (UC,  US,  same  variation) ;  Glendale,  Washoe  County,  Nevada,  Ken- 
nedy 1200  (NY,  UC,  same  variation);  Winslow,  Arizona,  Griffiths  5034;  California: 
Cienega,  Los  Angeles  County,  Braunton  633  (DS,  UC,  apparently  minor  variation  3, 
A.  carnosa  Nelson);  Ingomar,  Merced  County,  September  27,  1921,  Kennedy  (UC); 
West  Oakland,  September  23,  1897,  Davy  (UC,  genuine);  Petaluma,  September  1,  1888, 
Greene  (UC,  minor  variation  3,  A.  carnosa  Nelson);  Grand  Rond  Valley,  eastern  Oregon, 
Cusick  1759  (DS,  UC,  same  variation);  Coos  Bay,  Oregon,  House  4801  (US);  near 
Victoria,  British  Columbia,  Macoun  1854  (Gr). 

26.  Atriplex  patula  glabriuscula  (Edmonston). — Plant  with  widely  spreading  de- 
cumbent or  prostrate  branches  forming  circular  patches;  leaves  rather  small  (blades  of 
the  lower  ones  1.5  to  3  cm.  long,  1  to  2  cm.  wide),  petioled;  blade  triangular  with  short 
lobes  or  only  subhastately  angled  at  base  (the  upper  leaves  lanceolate),  dentate  or 
sometimes  entire;  glomerules  in  the  axils  of  the  upper  leaves;  fruiting  bracts  ovate  or 
triangular,  6  to  12  mm.  long,  broad  at  base,  the  margins  sinuate  or  low-dentate,  the 
face  with  small  clusters  of  tubercles  or  smooth  (fig.  30,  a  io  d).  {A.  glabriuscula  Ed- 
monston, Fl.  Shetland  39,  1845.)  Sea-shores  from  Newfoundland  to  Maine  and  very 
locally  to  Rhode  Island  and  casual  on  the  ballast  southward;  also  in  Iceland,  the  British 
Isles,  and  continental  Europe.  The  distribution  given  for  America  is  quoted  from 
Fernald  (Rhodora  23:262,  1921),  who  cites  a  long  series  of  collections.'  Only  two  col- 
lections have  been  examined  by  the  present  writers,  namely:  Charnay,  Labrador  Penin- 
sula, Quebec,  St.  John  90408  (Gr);  Sandy  Beach,  Miscou,  Gloucester  County,  New 
Brunswick,  Blake  6564  (Gr). 

2c.  Atriplex  patula  typica. — Plant  usually  erect,  the  branches  either  ascending  or 
widely  spreading,  strict  and  with  few  short  branches  in  dwarf  forms;  leaves  medium-sized, 
petioled;  blade  lanceolate  or  oblong,  rounded  or  narrowed  to  the  base,  not  hastate,  entire 
or  denticulate  or  rarely  with  a  pair  of  basal  lobes  pointing  forward ;  glomerules  scattered 
along  the  spike-like  branches  of  a  terminal  panicle  or  the  whole  inflorescence  spike-like 
in  reduced  forms;  fruiting  bracts  rhomboid  or  roundish,  3  to  6  mm.  long  or  up  to  8  mm. 
in  plants  of  good  soil,  narrowed  to  the  base,  the  margins  sparsely  denticulate,  but  the  teeth 
sometimes  very  obscure,  rarely  entire,  the  face  commonly  smooth.  {A.  patula  Linnaeus, 
Sp.  PI.  1053,  1753.)  Newfoundland  to  the  Gulf  of  Mexico,  southern  California,  and 
British  Columbia;  common  throughout  the  United  States  and  southern  Canada  in  a 
great  variety  of  forms,  also  in  Europe  and  Asia.     Type  locality,  Europe.     Collections: 

'In  the  paper  above  referred-  to,  Fernald  records  A.  patula  var.  bracleata  Westerlund,  Sveriges  Atripl,  57,  1861,  as 
occurring  in  North  Annerica.  The  record  is  based  upon  a  single  specimen  collected  near  the  mouth  of  George  River,  Cape 
Breton.  In  this  form  the  bracts  are  as  long  as  or  even  longer  than  those  of  glabriuscula,  but  the  inflorescence  is  not  leafy- 
bract«d.     In  many  respects  it  is  close  to  subspecies  obtuia. 


A.    PATULA.  251 

Birchy  Cove,  western  Newfoundland,  Fernald  and  Wiegand  S319  (Gr);  lower  St.  Law- 
rence River,  August  13,  1880,  Pringle  (US);  Black  Lake,  Quebec,  Fernald  and  Jackson 
12084  (Gr);  Little  Harbor,  New  Hampshire,  September  19,  1901,  Williams  (Gr);  eastern 
North  Carolina,  July,  1885,  McCarthy  (US);  Mobile,  Alabama,  June  4,  1893,  Mohr  (US); 
Oxford,  New  York,  August  13,  1884,  Conille  (US);  Toledo,  Ohio,  Sanford  2355  (US); 
Joliet,  Illinois,  Skeels  634  (US);  Madison,  Wisconsin,  August,  1887,  Holzinger  (US); 
North  Dakota,  September  14,  1901,  Lunnell  (Gr);  Fisher's  Ranch,  Wyoming,  Nelson 
5323  (UC);  Bay  Farm  Island,  Alameda,  California,  Jepson  5682  (Gr);  near  Victoria, 
British  Columbia,  Macoun  1857  (Gr,  US). 


Atriplex  palula  glabriuscula,  A.  p.  litoralis, 
and  A.  p.  spicata.  a  to  d,  A.  p.  glabriuscula, 
from  New  Brunswick  (.Blake  5664,  Gr):  o,  6, 
leaves;  c,  fruiting  branch;  d,  fruiting  bract,  e 
to  h,  A.  p.  litoralis,  from  Durham  County, 
England  (7182  UC),  the  bracts  after  Sow- 
erby  (Eng.  Bot  pi  1200):  e.  f,  leaves;  g,  h. 
fruiting  bracts,  i  to  I,  A.  p.  spicata,  from 
Main  Prairie.  California  (205332  UC):  i.  j. 
leaves;  k,  I,  fruiting  bracts.  All  leaves  X  1; 
bracts  X  2. 


^^ 


9      h 


2d.  Atriplex  patula  litoralis  (Linnaeus). — Plant  erect,  the  branches  ascending,  the 
lower  ones  from  a  decumbent  base;  leaves  long  but  narrow,  petioled;  blade  lanceolate  to 
linear,  attenuate  to  the  base,  never  hastate,  entire,  as  in  the  original  description,  undu- 
late or  sometimes  acutely  repand-dentate;  glomerules  in  long,  dense,  rarely  interrupted 
naked  paniculate  spikes  and  in  the  upper  axils;  fruiting  bracts  ovate  or  rhombic,  3  to  4 
mm.  long,  narrowed  at  the  base,  the  margins  sharply  denticulate,  the  face  tubercled 
(fig.  30,  e  to  h).  {A.  litoralis  Linnaeus,  Sp.  PI.  1054,  1753.)  Northeast  coast  from  Nova 
Scotia  to  New  Hampshire  and  inland  in  Ontario,  Ohio,  etc. ;  common  in  Europe.  Type 
locality,  Europe.  Collections:  Portage  Island,  Northumberland  County,  New  Bruns- 
wick, Blake  5680  (Gr) ;  Truro,  Colchester  County,  Nova  Scotia,  Fernald  and  Wiegand 
4266  (Gr);  North  Berwick,  Maine,  September,  1893,  Farlin  (Gr);  Little  Harbor,  New 
Hampshire,  September  19,  1901,  Williams  (Gr);  near  Pittsburgh,  Pennsylvania,  August 
18,  1869,  Porter  (Gr);  Benton  County,  Indiana,  Deam  21542  (Gr);  Kingston,  Ontario, 
September  1,  1897,  Fowler,  (Gr). 

2e.  Atriplex  patula  spicata  (Watson). — Plant  erect,  not  tall,  the  branches  rather 
rigidly  ascending;  leaves  medium-sized,  petioled,  the  upper  nearly  sessile;  blades  triangu- 
lar to  ovate,  usually  rhombic,  typically  broad  at  base  but  shortly  narrowed  to  the  petiole, 
coarsely  and  irregularly  sinuate-dentate;  glomerules  in  very  dense  spikes  terminating  the 
branches;  fruiting  bracts  ovate-oblong,  about  3  mm.  long,  the  margins  entire,  the  face 
not  appendaged  but  strongly  ribbed  or  furrowed  (fig.  30,  i  io  I).  {A.  spicata  Watson, 
Proc.  Am.  Acad.  9: 108,  1874.)  Middle  western  California.  Type  locality,  San  Joaquin 
Valley,  California,  according  to  Watson,  but  Livermore  Pass,  west  side  of  San  Joaquin 
Valley,  according  to  the  labels  and  field  book.     Collections  (all  in  California) :  Hollister, 


252 


GENUS   ATRIPLEX. 


San  Benito  County,  April  14,  1897,  Setchell  (UC);  type  collection,  May  31,  1862,  Brewer 
1190  (Gr,  NY) ;  Marsh  Creek,  Contra  Costa  County,  May,  1884,  Greene  (UC) ;  6  km.  west 
of  Byron,  Contra  Costa  County,  Hall  11801  (UC);  Lagoon  Valley.  Solano  County,  Sep- 
tember, 1891,  Jepson  (Herb.  Jepson,  type  of  A.  spicata  lagunita  Jepson,  minor  variation 
22);  Maine  Prairie,  Solano  County,  July  5,  1891,  Jepson  (UC);  near  Dunnigan,  Yolo 
County,  Siinchfield  357  (DS);  near  Williams,  Colusa  County,  Heller  12394  (DS,  SF);  rice 
fields  near  Willows,  Glenn  County,  August  9,  1921,  Kennedy  (UC);  west  of  Norman, 
Glenn  County,  Hall  11009  (UC). 


-Airiplex  patula  obtusa  and  A.  p.  alaskensis.  abo  e,  A.  p.  obtusa  from  the  region  of  Humboldt  Bay,  California  (146161 
and  162361  UC);  a,  b,  c,  leaves;  d,  e,  fruiting  bracta.  /  to  A,  A.  p.  alaskensis  from  the  type  collection  (Gr): 
/,  twig;  g,  h,  fruiting  bracts.     All  leaves  and  twigs  X  1;  bracts  X  2. 


2/.  Atriplex  patula  obtusa  (Chamisso). — Plant  usually  erect,  with  widely  spreading 
upcurved  branches,  simple-stemmed  in  reduced  forms;  leaves  long  and  narrow,  short- 
petioled;  blade  lanceolate  to  linear,  attenuate  to  the  base  (the  lower  obtuse  at  apex,  hence 
the  name),  entire  or  crenulate,  occasionally  with  1  or  2  short  ascending  lobes  from  below 
the  middle;  glomerules  in  short  dense  paniculate  spikes  and  in  the  upper  axils;  fruiting 
bracts  broadly  ovate  or  rhomboidal,  4  to  12  mm.  long,  rounded  to  the  base,  the  margins 
entire,  the  face  smooth  or  rarely  with  a  few  minute  appendages  (fig.  31,  a  to  e).  {A. 
angustifoUa  var.  obtusa  Chamisso,  Linnaea  6:569,  1831.)  Pacific  Coast  from  northern 
Alaska  to  middle  California.  Type  locality,  Eschscholtz  Bay,  Kotzebue  Sound,  Alaska. 
Collections :  Fort  St.  Michaels,  Norton  Sound,  Alaska,  1865-66,  Bannister  (Gr) ;  near  Kar- 
luk  Village,  Alaska,  abundant  on  sandy  and  muddy  beach  near  high-tide  line,  August, 
1902,  Home  (NY);  Halibut  Cove,  Cook  Inlet,  Alaska,  Coinlle  and  Kearney  2451  (US, 
type  of  A.  drymarioides  Standley,  minor  variation  5);  Loring,  southwestern  Alaska, 
Howell  1656  (UC);  San  Juan  Harbor,  Vancouver  Island,  Rosendahl  2060  (Gr,  NY); 
Shoalwater  Bay,  Washington,  August  17,  1907,  McGregor  (DS);  California:  near  mouth 
of  Mad  River  Slough,  Humboldt  County,  not  common,  Tracy  3555  (Gr,  UC,  US) ;  mouth 
of  Elk  River,  Humboldt  County,  Tracy  2393  (UC);  West  Oakland,  September  23,  1897, 
Davy  (UC) ;  Fitchburg,  Alameda  County,  November  13,  1899,  Nott  (UC). 

2g.  Atriplex  patula  zosteraefolia  (Hooker). — Plant  ascending,  the  branches 
mostly  ascending  but  weak  and  slender,  some  decumbent;  leaves  2  to  4  cm.  long,  or  the 
lower  probably  much  longer,  petioled;  blade  linear,  narrow  at  base,  not  hastate,  entire; 


A.    PATULA.  253 

glomerules  in  short  axillary  spikes  and  in  the  upper  axils;  fruiting  bracts  linear,  8  to  12 
mm.  long,  the  margins  entire,  the  face  smooth.  {Chenopodium  (?)  zosteraefolium  Hooker, 
Fl.  Bor.  Am.  2:127,  1838.)  Southern  Alaska  and  probably  northwestern  Washington. 
Type  locality,  British  Columbia  and  Straits  of  Juan  de  Fuca.  Collections :  Type  collec- 
tion (Gr,  fragment  only) ;  Prince  of  Wales  Island,  Alaska,  Walker  914  (Gr). 

2h.  Atriplex  PATULA  ALASKENSis  (Watson). — Plant  erect  or  ascending,  stout  (suc- 
culent?), the  branches  ascending  from  a  spreading  base;  leaves  large,  petioled;  blade  ovate 
to  oblong  or  lanceolate,  cuneate  at  base,  entire  or  with  1  or  2  short  lobes  from  below  the 
middle  and  then  subhastate,  or  rarely  repand-denticulate ;  glomerules  in  the  leaf -axils; 
fruiting  bracts  oblong  to  ovate-orbicular,  6  to  20  mm.  long,  becoming  thick  and  spongious 
at  the  rounded  base,  the  broad  margins  entire,  the  face  smooth  (fig.  31,  /  to  /i).  {A. 
alaskensis  Watson,  Proc.  Am.  Acad.  9:108,  1874.)  Coast  of  Alaska.  Type  locality. 
Barlows  Cove,  Alaska.  Collections:  Type  collection,  Kellogg  176  (Gr,  US);  Karluk 
Village,  about  high-tide  line,  August,  1902,  Home  (NY);  Kodiak,  Mylroie  1^2  (NY, 
young,  but  probably  this). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Atriplex  alaskensis  Watson,  Proc.  Am.  Acad.  9: 108,  1874.—^.  patula  alaskensis. 

2.  A.  ANGUSTIFOLIA  var.  obtusa  Chamis.so,  Linnaea  6:569,  1831. — A.  palula  obtusa. 

3.  A.  CARNOSA  Nelson,  Bot.  Gaz.  .34:361,  1902.— A  remarkable  variation  of  A.  palula  hastata,  perhaps  to  be 
admitted  as  a  distinct  subspecies.  Stems  stout,  erect,  with  rigidly  ascending  branches;  leaves  thick,  succulent, 
somewhat  leathery  on  drying,  seldom  truly  hastate,  but  the  principal  ones  with  a  prominent  spreading  lobe  from 
each  of  the  basal  angles;  fruiting  spikes  dense,  almost  continuous,  bracts  more  persistent  than  in  the  common 
coastal  form,  usually  4  or  5  mm.  long,  thick,  fleshy.  The  type  is  Nelson  8036  from  Laramie,  Wyoming.  This 
form  is  common  throughout  the  alkaline  districts  from  the  Rocky  Mountains  to  the  Pacific,  in  which  area 
genuine  hastata  occurs  only  sporadically  and  perhaps  as  an  introduction.  In  California  carnosa  grows  also 
within  reach  of  tide-water,  but  is  not  known  to  mix  with  hastata,  although  some  collections  can  not  be  placed 
with  certainty  in  either  of  the  forms.  In  Nevada  the  fruiting  bracts  sometimes  become  much  enlarged  and 
vary  also  in  their  sculpturing  (see  No.  17). 

4.  A.  DioECA  Rafinesque,  Am.  Mo.  Mag.  2 :  176,  1818.  Not  technically  published,  since  Rafinesque  men- 
tioned the  name  only  incidentally  in  a  review  of  Pursh's  Flora.  Applied  to  the  plant  here  referred  to  A.  palula 
hastata. 

5.  A.  DRYMARioiDEs  Standley,  N.  Am.  Fl.  21:40,  1916.— Apparently  a  much  reduced  form  of  A.  patula 
obtusa.  The  type  specimens,  from  Halibut  Cove,  Cook  Inlet,  Alaska,  are  only  5  to  10  cm.  high  and  have  broadly 
oblong,  obtuse  lower  leaves,  which  are  so  shortly  cuneate  at  the  base  as  to  appear  almost  sessile.  Another 
collection,  from  Peril  Straits,  Baranoff  Island  {Stephens  69,  UC)  is  identical  in  habit  and  fruits,  some  of  which, 
however,  are  more  mature  and  hence  more  like  those  of  obtusa.  The  leaves  vary  from  nearly  as  broad  and  sub- 
sessile  as  those  of  the  type  to  linear,  and  some  are  plainly  petioled.  This  collection  from  Baranoff  therefore 
establishes,  almost  beyond  doubt,  that  drymarioides  is  a  dwarf  state  of  obtusa.  Similar  reductions  of  subspecies 
hastata  and  typica  are  well  known. 

6.  A.  GMELiNi  Meyer,  Mem.  Acad.  St.  Petersb.  VI.  4=:  160,  1838.— The  code  name  for  A.  patula  obtusa  when 
this  is  given  specific  rank.  The  name  obtusa  is  here  selected,  since  it  was  first  used  for  this  subspecies,  although 
as  a  variety,  and  because  of  its  descriptive  value. 

7.  A.  GMELiNi  /3  zosTERAEFOLiA  Moquin,  in  DeCandoUe,  Prodr.  13^:97,  1849. — A.  patula  zosteraefolia. 

8.  A.  HALiMoiDES  Rafinesque,  Am.  Mo.  Mag.  2:176,  1818.— Generally  regarded  as  the  same  as  A.  patula 
hastata. 

9.  A.  HASTATA  Linnaeus,  Sp.  PI.  1053,  1753. — A.  patula  hastata.  Has  place  priority  over  patula  in  the 
Species  Plantarum,  but  usage  as  well  as  descriptive  value  is  in  favor  of  this  latter  as  the  specific  name,  which 
furthermore  is  permissible  under  the  International  Code. 

10.  A.  HASTATA  LiTORALis  Pons,  Nuov.  Giorn.  Bot.  Ital.  II,  9:419,  1902. — A.  patula  litoralis. 

11.  A.  HASTATA  PATULA  Pons,  1.  c,  417,  1902. — A.  patula  typica.     (See  note  under  No.  9.) 

12.  A.  JOAQUINIANA  Nelson,  Proc.  Biol.  Soc.  Wash.  17:99,  1904. — A.  patula  spicata. 

13.  A.  LACiNiATA  /3  AMERICANA  Torrey,  Fl.  U.  S.  293, 1824.— A.  patula  hastata. 

14.  A.  LAPATHiFOLiA  Rydberg,  Mem.  N.  Y.  Bot.  Gard.  1 :  133,  1900.— Probably  the  same  as  No.  3  of  this 
list  and  therefore  part  of  A.  patula  hastata.  The  type  is  a  nearly  leafless  plant  with  bracts  as  in  genuine  hastata. 
It  came  from  Fridley,  Montana. 

15.  A.  LITORALIS  Linnaeus,  Sp.  PI.  1054,  1753. — A.  patula  litoralis. 

16.  A.  PATULA  var.  hastata  Gray,  Man.  ed.  5,  409,  1867. — A.  patula  hastata. 


254  GENUS   ATRIPLEX. 

17.  A.  PATTJLA  HASTATA,  but  with  much  enlarged  bracts,  the  other  characters  similar  to  those  of  A.  camosa 
Nelson  (No.  3  of  this  list).  In  a  collection  from  alkaline  roadsides  east  of  Sparks,  Nevada  {Hall  11232,  UC),  the 
mature  bracts  of  one  plant  are  in  part  of  the  usual  type  and  3  to  4  mm.  long,  while  others  on  the  same  branches 
vary  through  all  intermediate  sizes  up  to  13  mm.  long  and  nearly  as  wide.  Some  of  these  larger  bracts  are 
smooth  on  the  faces,  others  tuberculate  or  cristate. 

18.  A.  PATULA  var.  litoralis  Gray,  1.  c. — Based  upon  A.  liioralis  Linnaeus,  therefore  the  same  as  A.  patvla 
IHoralis,  although  Gray's  description  includes  also  the  lance-leaved  A.  p.  typica. 

19.  A.  PATULA  var.  subspicata  Watson,  Proc.  Am.  Acad.  9:107,  1874. — Based  upon  Chenopodium  sub- 
spicatum  Nuttall,  No.  24  of  this  list. 

20.  A.  ptmsHiANA  Moquin,  Chenop.  Enum.  .55,  1840. — Referred  by  Standley  (1.  e.)  to  A.  hastata. 

21.  A.  SPICATA  Watson,  Proc.  Am.  Acad.  9:108,  1874. — A.  patula  spicata. 

22.  A.  SPICATA  var.  lagunita  Jepson,  Fl.  W.  Mid.  Calif.  179,  1901.— The  original  description  in  full  is  as  fol- 
lows: "Very  slender,  simple,  5  to  8  in.  high;  fruiting  bracts  1}4  lines  long.  Lagoon  Valley,  Solano  County, 
California,  September,  1891."  The  types  are  nearly  leafless  fruiting  plants  scarcely  distinguishable  from  spicata, 
save  by  their  small  size  and  slender  habit. 

23.  A.  zosteeaefoua  Watson,  Proc.  Am.  Acad.  9:109,  1874.— Based  upon  Chenopodium  zosteraefolium 
Hooker  and  therefore  A.  patula  zosteraefolia. 

23a.  A.  subspicata  Rydberg,  Bull.  Torr  Club  33:137,  1906.  Based  upon  Chenopodium  suhspicatum, 
which  see. 

24.  Chenopodium  subspicatum  Nuttall,  Genera  1 :  199,  1818.— A  form  of  A.  patula  hastata  very  close  to,  if 
not  identical  with,  the  later  A.  camosa  Nelson,  of  this  list.  A  specimen  in  the  herbarium  of  the  Philadelphia 
Academy  of  Sciences  is  labeled  "Upper  Louisiana,  Niiltall,"  which  is  probably  a  portion  of  the  type  collection. 
This  has  the  usual  moniliform  staminate  inflorescences  and  thick  deltoid  leaves  characteristic  of  the  camosa 
form.  The  type  locality  is  saline  soils  around  the  Mandan  village,  Missouri.  This  was  included  in  the  original 
Territory   of   Louisiana. 

25.  C.  (?)  ZOSTERAEFOLIUM  Hooker,  Fl.  Bor.  Am.  2:127,  1838. — A.  patula  zosteraefolia.  Hooker  distin- 
guished two  forms  in  the  type  collection,  one  with  leaves  linear  and  scarcely  2  mm.  wide,  the  other  with  leaves 
linear-oblong,   broader,  and  shorter. 

RELATIONSHIPS. 

Atriplex  patula  evidences  a  considerable  degree  of  evolutionary  advancement  along 
certain  lines,  notably  the  entire  suppression  of  the  perianth  and  the  production  of  a 
large  variety  of  forms  adapted  to  diversified  conditions.  However,  it  retains  the 
inferior  position  of  the  radicle  and  the  monoecious  habit,  these  traits  indicating  that  it 
diverged  from  the  main  line  at  a  very  early  period.  The  bracts  also  are  still  either 
distinct  nearly  to  the  base,  or  the  margins  are  united  only  along  the  lower  portion. 
The  most  closely  related  species  seem  to  be  of  the  rosea  group,  from  all  of  which,  how- 
ever, it  differs  in  the  non-cartilaginous  bracts  and  other  characters.  There  is  no 
direct  connection  with  any  other  group. 

The  taxonomic  segregates  of  A.  patula  are  more  numerous  than  those  of  any  other 
species.  The  16  species  and  varieties  proposed  by  taxonomists  from  among  the  North 
American  forms  may  be  taken  as  only  the  beginning,  since  little  attention  has  as  yet 
been  given  to  most  of  the  characters  and  combinations  of  characters  used  as  the  basis 
for  segregates  in  Europe,  where  the  total  number  of  these  considerably  exceeds  100. 
Something  as  to  the  difficulty  of  organizing  these  units  was  expressed  by  Ascherson  and 
Graebner  (Syn.  Mitteleur.  Fl.  5:123,  1913),  who  state  that  A.  patula,  even  exclusive  of 
litoralis  and  hastata,  which  they  treat  as  distinct  collective  species,  is  so  extraordinarily 
variable  in  almost  all  its  parts  that  it  appears  impossible  to  bring  the  proposed  forms 
into  any  sort  of  a  classification  except  on  the  basis  of  single  characters.  These  authors 
Ust  34  named  variations  of  A.  patula,  the  descriptions  taken  mostly  from  other  sources, 
often  with  the  remark  that  they  have  almost  no  value.  Fourteen  variations  of  hastata 
are  also  enumerated.  The  characters  most  commonly  used  in  Europe  are  habit  and 
color  of  plant,  and  size,  texture,  and  dentation  of  the  bracts  and  leaves.^ 

A  much  more  satisfactory  treatment  is  given  for  the  forms  which  occur  in 
the  British  Islands,  by  Mo.ss  and  Wilmott  (in  Moss,  Cambridge  Brit.  Fl.  2: 170-179,  1914). 
Here  four  species  are  recognized,  litoralis,  patula,  hastata,  and  glabriuscula,  each  with  a 

•  Turesson,  G.     Hereditas  3:211,  1922. 


A.    PATULA. 


255 


number  of  varieties  and  minor  forms.  The  difficulties  encountered  and  the  unsatis- 
factory nature  of  the  results  are  evidenced  by  the  overlapping  of  the  key  characters,  the 
occasional  lack  of  concordance  between  these  and  the  descriptions,  the  admitted  diffi- 
culty of  placing  many  of  the  forms,  at  least  as  to  variety,  and  the  frequency  of  supposed 
hybrids. 

In  order  to  avoid  such  confusion  as  exists  in  the  European  literature,  it  seems  wise 
to  retain  all  of  the  "patula  group"  in  one  collective  species  and  to  admit  under  this  a 
limited  number  of  closely  defined  subspecies.  The  precedents  of  Gray  and  Watson  are 
followed  in  adopting  patula  for  the  specific  name,  notwithstanding  the  fact  that  has- 
tata  appears  before  it  on  the  page  where  both  were  originally  published.  The  distinc- 
tions between  these  two  lie  wholly  in  the  shape  of  the  leaves  and  of  the  bracts.  Since 
these  differences  vanish  when  intermediate  forms  occur,  and  since  the  shape  of  the 
bract  is  looked  upon  only  as  another  expression  of  the  leaf-character,  the  criteria  can 
have  not  more  than  subspecific  value.  On  the  other  hand,  these  two  subspecies  are 
much  more  than  ecologic  forms.  Over  much  of  the  area  of  distribution  they  remain 
entirely  distinct  and  easily  recognizable,  even  when  growing  side  by  side. 


Table  24. — Variation  in  Atriplex  patula  hastata  and  A.  patula  typica. 


Herbarium. 

Leaves. 

Average 
size  of 

bracts. 

Margin  of  bracts. 

Face  of  bracts. 

Subspecies  haslala: 

Bridgeport,  Conn 

Maryland 

282946  US 

939158  us 
295716  US 

647229  US 
490849  US 
267817  US 
271023  US 
161058  UC 

644691  US 

224223  US 

51223  UC 

7117  UC 

75369  UC 
646240  US 

Triangular-hastate. . 
Do 

mm. 

3  by2.8 

4.6       4 
6.5       6 

4  4 
6           6 

5  5 
4            5 
5.5       5 

4           3 

6  6 

8           6 
6           4.5 

4.5       4.5 
4           3 

Dentate 

Somesmooth,8ome 
bituberculate. 

Smooth. 

Some  smooth,  some 
bituberculate. 

Sparsely  murioate. 

Smooth. 
Do. 

Cristate. 

Cristate  or  smooth. 

Smooth. 
Do. 
Do. 
Smooth   or  tuber- 

culate. 
Smooth. 

Smooth  or  bituber- 
culate. 

Entire  or  few-toothed .  . 

Ithaca,  N.  Y 

Freeport,  111. 

Do 

Do 

Urbana,  111 

Do 

Laramie,  Wyo 

St.  George,  Utah 

Eureka   Calif 

Triangular 

Sinuate 

Do 

Lanceolate 

Do 

Entire  or  low-dentate .  . 

Some  denticulate 

Denticulate 

Sparsely  dentate 

Dentate 

Do 

Low-denticulate 

Subspecies  typica: 

Canton,  N.  Y 

Wilmington,  N.  C 

Fisher's  Ranch,  Wyo.. 
Berkeley,  Calif 

Alviso,  Calif. 

Do 

Do' 

Joliet   III 

Linear 

'  Lower  leaves  wanting;  probably  referable  to  typica  on  the  character  of  the  shape  of  the  bracts. 

Various  attempts  have  been  made  to  differentiate  these  and  other  forms  on  the  basis  of 
size  and  sculpturing  of  the  bracts.  A  hint  as  to  the  unreliabiHty  of  these  criteria  is  given 
in  the  subjoined  table.  The  tabulation  of  a  much  more  extended  series  has  been  made, 
but  since  it  merely  confirms  the  results  of  the  first  examination  it  is  not  given. 

The  subspecies  glahriuscula  is  placed  between  the  two  just  discussed  because  of  its 
evident  derivation  from  hastata,  from  which  it  scarcely  differs,  except  in  the  larger  upper 
leaves  which  persist  throughout  the  inflorescence.  It  is  much  more  abundant  in  Europe 
than  on  this  continent  and  seems  to  be  especially  suited  to  boreal  conditions.  The  close 
similarity  in  most  characters  to  those  of  A.  maritima,  especially  the  tendency  toward  a 
hardening  of  the  bracts,  suggests  that  glahriuscula  may  represent  the  primitive  stock  of 
the  group  of  species  sometimes  known  as  section  Obionopsis.  The  subspecies  litoralis 
may  be  looked  upon  as  a  development  from  patula  in  a  direction  opposite  to  that  of  has- 
tata, since  its  leaves  have  undergone  the  greatest  amount  of  reduction  in  width.     In 


256  GENUS   ATRIPLEX. 

North  America  it  is  apparently  confined  to  the  easterly  part  of  the  continent.  Speci- 
mens from  the  Pacific  Coast  referred  here  are  now  found  to  belong  to  one  or  another 
of  the  following  enumeration. 

The  remaining  subspecies  differ  from  all  of  the  preceding  in  their  fruiting  bracts,  the 
margins  of  which  are  narrower  and  strictly  entire.  (For  a  valuation  of  this  feature  see 
p.  242.)  They  belong  entirely  to  the  Pacific  Coast  and  the  connections  with  Asiatic  forms 
indicate  that,  with  the  possible  exception  of  spicaia,  all  have  reached  America  by  way  of 
Siberia.  They  are  most  abundant  along  the  coast  of  Alaska  and  on  the  adjacent  islands, 
becoming  less  common  toward  the  south,  none  extending  beyond  middle  California. 
The  subspecies  spicata  is  of  doubtful  origin,  but  it  seems  most  like  hastata,  except  for  the 
bract  differences  just  mentioned.  Little  is  known  of  its  variations  or  life  history.  The 
numerous  salient  teeth  of  the  leaves  are  usually  distinctive,  but  the  same  type  of  foliage 
is  known  also  in  subspecies  hastata  (for  example,  Newfoundland,  Wagborne  49,  Gr).  Sub- 
species obtusa  is  much  more  widely  distributed  and  ranges  west  well  into  Siberia,  where 
it  is  usually  known  as  A.  gmelini.  In  the  United  States  it  has  been  unaccountably  con- 
fused with  both  patula  and  litoralis,  but  differs  from  both  in  the  bracts.  These  are  not 
only  entire,  but  also  have  a  tendency  toward  the  development  of  an  elongated  lanceolate 
tip,  so  that  the  whole  bract  is  considerably  longer  than  in  those  forms.  It  has  also  a 
characteristically  strict  or  ascending  habit  of  growth,  which  enables  one  to  recognize  it 
on  general  appearance.  Little  is  definitely  known  concerning  subspecies  zoster aefolius, 
found  only  in  a  few  collections  made  along  the  Straits  of  Juan  de  Fuca.  Further  field 
studies  may  demonstrate  the  wisdom  of  Hooker's  suggestion,  namely,  that  it  is  perhaps  a 
luxuriant  state  of  subspecies  obtusa  (Hooker,  Fl.  Bor.  Am.  2:127,  1838).  Fernald  (Rho- 
dora  23:264,  1921)  recently  has  recorded  A.  patula  bracteata  Westerlund  (Sveriges  Atripl., 
57,  1861)  from  Nova  Scotia.  This  is  much  like  obtusa  in  the  foliage  and  bracts,  but  the 
latter  frequently  are  toothed. 

The  subspecies  alaskensis  is  so  luxuriant  in  its  foliage  and  the  margins  of  the  bracts  are 
so  remarkably  developed  that  it  is  the  most  outstanding  of  all  of  the  forms  here  brought 
under  A.  patula.  The  bracts  are  usually  described  as  spongious-thickened,  but  the 
thickening  is  perhaps  no  greater  in  proportion  to  the  size  of  the  body  than  sometimes 
takes  place  in  other  subspecies,  notably  spicata.  The  mature  bracts  are  so  large  (.6  to 
20  mm.  long)  that  this  feature  alone  might  seem  to  constitute  a  specific  criterion,  but 
other  subspecies  have  bracts  which  not  infrequently  reach  10  or  12  mm.  and  even  in 
hastata,  where  these  structures  are  usually  much  smaller,  occasionally  plants  are  found 
in  which  they  reach  12  mm.  in  length  (minor  variation  17).  While  this  does  not  over- 
throw alaskensis  as  a  valuable  taxonomic  unit,  it  does  demonstrate  the  inherent  capacity 
of  other  subspecies  nearly  to  duplicate  its  most  characteristic  features.  The  radicle 
has  been  described  as  superior,  but  probably  it  is  no  more  so  than  in  the  other  sub- 
species. Dissections  have  been  made  of  the  type  material,  but  the  embryo  was  so 
deformed  as  to  render  impossible  a  positive  determination  of  the  position. 

ECOLOGY  AND  USES. 

Atriplex  patula  is  typically  a  halophytic  annual  widely  distributed  in  salt-marshes  and 
on  alkali-flats.  The  subspecies  hastata  and  typica  in  particular  often  form  pure  consocies 
in  saline  areas,  though  they  are  usually  more  or  less  mixed  with  other  marked  halo- 
phytes.  They  frequently  invade  fallow  fields,  especially  in  the  arid  regions,  where  they 
constitute  a  pioneer  stage  in  the  short  subsere.  The  relation  of  hastata  to  the  salt-content 
of  the  soil  has  been  determined  by  Kearney  and  his  associates  to  range  from  0.33  to  1.33 
per  cent  in  the  first  foot  and  from  0.46  to  3.3  per  cent  in  the  third  foot. 

While  the  common  forms  of  this  species  were  formerly  used  for  greens  in  the  Old 
World,  this  is  rarely  if  ever  the  case  in  this  country.  Hastata  and  typica  are  grazed  to 
some  extent,  but  are  rarely  abundant  enough  to  be  of  much  importance. 


A.    CALIFORNICA.  257 

3.  ATRIPLEX  CALIFORNICA  Moquin,  in  DeCandolle,  Prodr.  13':  98,  1849.     Plate  39. 

Prostrate  perennial  herb  (the  only  North  American  Atriplex  with  a  fusiform  taproot, 
this  slender,  elongated,  fleshy  or  spongious),  the  stems  spreading  to  form  tangled  mats 
or  beds  1  to  2  dm.  deep  but  up  to  10  dm.  or  more  across,  the  ultimate  twigs  erect  or  ascend- 
ing; branches  wiry,  not  angled,  white-mealy,  glabrate  and  then  stramineous;  leaves  alter- 
nate or  the  lower  opposite,  crowded,  sessile,  lanceolate  or  ovate-lanceolate,  all  much 
narrowed  to  the  base,  acute  at  apex,  0.8  to  2  or  rarely  3  cm.  long,  0.2  to  0.4  cm.  wide, 
entire,  comparatively  thin,  heavily  coated  with  a  gray  tomentum  but  the  general  hue 
often  greenish,  obscurely  1-nerved;  flowers  monoecious,  the  two  kinds  mixing  in  the  leaf- 
axils,  the  staminate  also  in  approximate  glomerules  arranged  in  nearly  naked  terminal 
spikes;  perianth  4-cleft  in  the  staminate  flowers,  wanting  in  the  pistillate;  fruiting  bracts 
sessile,  compressed,  separate  nearly  to  the  base,  ovate,  acute,  3  to  5  mm.  long,  2.5  to 
4  mm.  broad,  entire,  the  faces  not  appendaged,  1-nerved  under  the  dense  scurf;  seed  2 
mm.  long,  black;  radicle  inferior  or  sometimes  lateral,  never  superior. 

Sandy  coasts  along  the  Pacific  Ocean,  from  slightly  north  of  San  Francisco,  California, 
to  Cedros  Island,  Lower  California.  Type  locality,  California.  Collections,  all  in 
California  or  Lower  California:  Bodega  Point,  Sonoma  County,  Eastwood  4802  (SF); 
Point  Reyes,  Marin  County,  Davy  6764  (UC) ;  Mare  Island,  San  Francisco  Bay,  Septem- 
ber 7,  1874,  Greene  (Gr);  West  Berkeley,  Michener  and  Bioletti  561a  (US);  Alameda 
Marshes,  September  17,  1898,  Davy  (UC);  Pillar  Point,  San  Mateo  County,  Baker  174S 
(Gr,  SF,  UC,  US) ;  Santa  Cruz,  April  15,  1897,  Setchell  (UC) ;  near  Point  Pinos,  Monterey 
County,  Heller  6746  (DS,  UC,  US);  San  Simeon,  San  Luis  Obispo  County,  August, 
1885,  Brandegee  (UC);  Santa  Maria,  June,  1894,  Alderson  (UC);  Surf,  Santa  Barbara 
County,  Elmer  4OII  (NY,  US);  Carpenteria,  Santa  Barbara  County,  Hall  10953  (CI); 
Santa  Rosa  Island,  June,  1888,  Brandegee  (UC) ;  San  Miguel  Island  (according  to  Bran- 
degee, Zoe  1:144,  1890);  Santa  Cruz  Island,  1919,  Swain  (SF);  Anacapa  Island,  1901, 
Hemphill  (UC) ;  Santa  Catalina  Island,  rare,  September,  1898,  Trask  (UC) ;  San  Nicholas 
Island,  April,  1901,  Trask  (Gr,  NY);  San  Clemente  Island,  Mearns  4074  (DS,  US); 
Redondo,  Los  Angeles  County,  Braunton  267  (UC) ;  La  JoUa,  San  Diego  County,  Clem- 
ents 56  (UC,  US);  Initial  monument,  United  States-Mexico  line,  July  1,  1899,  Bran- 
degee (UC);  South  Coronado  Island,  Parish  8839  (DS,  UC);  Todos  Santos  Bay,  Orcutt 
1269  (Gr,  US);  San  Quentin  Bay,  Palmer  718  (Gr,  NY,  US);  El  Rosario,  March  21, 
1889,  Brandegee  (UC);  Cedros  Island,  April  30,  1885,  Greene  (US). 

RELATIONSHIPS. 

Atriplex  calif ornica  is  not  closely  related  to  any  other  species,  at  least  not  to  any  known 
in  North  America.  It  is  primitive  in  its  dioecious  habit,  inferior  radicle,  and  the 
absence  of  cohesion  between  the  bracts.  Furthermore,  the  pistil  is  much  less  reduced  in 
the  staminate  flowers  than  it  is  in  the  other  species.  Since  no  other  exhibits  this  com- 
bination of  fundamental  characters,  it  is  almost  certainly  a  derivative  of  some  ancestral 
stock  not  now  here  represented,  and  therefore  belongs  in  a  section  or  subgenus  by  itself. 
If  A.  hortensis  is  taken  as  the  most  primitive  Atriplex,  then  calif  ornica  represents  an 
advance  through  the  complete  suppression  of  the  perianth,  but  without  the  develop- 
ment of  certain  features  which  have  been  attained  on  the  hortensis  line.  The  patula 
and  rosea  groups  are  the  only  others  in  which  the  radicle  is  inferior,  and  these  are  far 
removed  from  calif  ornica  in  almost  all  other  characters. 

In  appearance  and  in  its  ecologic  relations  this  species  is  similar  to  A.  decumbens,  but 
probably  there  is  no  direct  phylogenetic  connection  between  them;  the  former  differing 
in  its  fusiform  root,  monoecious  habit,  mostly  alternate  leaves,  thin  and  distinct  fruiting 
bracts,  and  inferior  radicle,  as  well  as  in  minor  details. 

The  radicle  in  A.  calif  ornica  is  described  as  inferior,  and  this  is  strictly  true  as  far  as 
most  of  the  embryos  are  concerned.     Occasionally,   however,  the  radicle  is  carried 


258  GENUS    ATRIPLEX. 

slightly  above  the  normal  position  and  thus  becomes  lateral.  This  appears  to  be  the 
beginning  of  a  tendency  which  has  culminated  in  the  superior  position  common  in  most 
species  of  the  genus. 

ECOLOGY  AND  USES. 

Atriplex  calif ornica  sometimes  forms  pure  socies  of  limited  extent  in  saline  marshes, 
but  it  is  usually  associated  with  such  dominants  as  Distichlis  or  Haplopappus,  outside 
the  Salicornia  zone.  It  occurs  also  on  the  more  stable  strand  and  dunes,  and  especially 
in  the  saline  valleys  between  inner  dunes.  It  is  unique  in  the  genus  in  the  development 
of  a  slender  fusiform  root  for  storage.  The  flowers  bloom  during  an  exceptionally  long 
season,  beginning  in  April  and  lasting  to  October. 

This  species  is  of  little  value  for  grazing,  owing  to  its  small  size,  its  halophytic  char- 
acter, and  its  lack  of  abundance.  The  roots  are  said  by  Greene  (Pittonia  1:207,  1888) 
to  be  sweet  and  well-flavored,  but  they  are  not  used.  Recent  observations  along  the 
coast  of  middle  California  indicate  that  they  are  exceedingly  bitter,  at  least  in  some 


4.  ATRIPLEX  MARITIMA  Hallier,  Bot.  Zeit.  21,  beUag  1:10,  1863.    Plate  38. 

Spreading  or  prostrate  annual  herb  with  stems  0.5  to  5  dm.  long,  branched  from  the 
base;  branches  thick  but  weak  and  with  a  tendency  to  droop,  scarcely  angled,  nearly 
glabrous,  stramineous,  the  bark  smooth  and  persistent;  leaves  mostly  alternate,  the 
lowest  opposite,  petioled,  suborbicular  to  ovate  or  rhombic-ovate,  cuneate  at  base,  very 
obtuse  to  acutish  and  mucronulate  at  apex,  2  to  4  cm.  long,  1  to  2.5  cm.  wide,  irregularly 
repand-dentate  with  mostly  obtuse  teeth  or  some  of  the  upper  ones  nearly  entire,  rather 
densely  furfuraceous  on  both  sides,  soft;  flowers  monoecious,  the  staminate  in  small 
glomerules  in  the  upper  axils  and  in  short  dense  terminal  spikes,  these  1  cm.  or  less 
long,  the  pistillate  in  axillary  glomerules  beneath  the  staminate,  some  of  the  interme- 
diate glomerules  with  both  staminate  and  pistillate  flowers;  perianth  5-cleft,  wanting  in 
the  pistillate  flowers;  fruiting  bracts  sessile  or  subsessile,  compressed,  united  to  above 
the  middle,  rhombic-hastate,  widest  at  the  middle,  6  to  9  mm.  long,  6  to  9  mm.  wide, 
becoming  hard  and  cartilaginous  at  least  as  to  body,  entire  except  at  the  angles,  either 
with  a  few  strong  flattened  tubercles  or  these  wanting,  strongly  3-nerved  and  reticulate; 
seed  3  to  4  mm.  long,  dull  brown;  radicle  inferior,  ascending. 

On  sandy  beaches  of  Quebec  and  New  Brunswick;  also  on  shores  of  northwestern 
Europe.  Type  locality,  England.  Collections:  Fox  Island,  New  Brunswick,  Blake 
6692  (Gr);  Grindstone  Island,  Magdalena  Islands,  Quebec,  Fernald,  Long,  and  St. 
John  7397  (Gr,  UC,  not  mature  but  probably  of  this  species).  Additional  localities  are 
cited  by  Blake  (Rhodora  17:86,  1915). 

MINOR  VARIATIONS  AND  SYNONYMS. 

Little  is  known  concerning  the  forms  of  this  species  in  America,  since  it  has  been  but  little  collected.  A 
number  of  varieties  have  been  named  in  Europe.  The  complicated  synonymy  of  the  species  is  discussed  by 
Blake  (1.  c.) 

1.  Atriplex  arenaria  Woods,  Phytologist  3 :  593,  1849.— An  older  name  for  this  species  but  antedated  by 
A.  arenaria  Nuttall.  Although  Nuttall's  species  is  reduced  in  the  present  paper  to  a  subspecies  ol  A.  pentandra, 
Wood's  name  is  not  here  taken  up  for  maritima,  as  has  been  done  by  Ascherson  and  Graebner  and  other  Euro- 
pean botanists,  because  of  its  long  use  for  the  Nuttallian  species. 

2.  A.  ROSEA  var.  arenaria  Westerlund,  Sver.  Atr.  32,  1861,  and  Linnaea  40:142,  1876.— An  apparently 
necessary  reduction  of  A.  marilima  to  its  most  closely  related  species. 

3.  A.  sabulosa  Rouy,  Bull.  Soc.  Bot.  Fr.  37:20,  1890.—^.  marilima. 

RELATIONSHIPS. 
This  is  perhaps  not  more  than  a  subspecies  of  A.  rosea,  since  the  diff'erences  are  only 
those  of  habit  and  the  size  of  the  bracts  and  seeds.     However,  it  is  so  little  known  in 
America  that  a  decision  as  to  its  reduction  may  be  left  for  the  future,  as  this  would 


A.    MARITIMA — A.    ROSEA.  259 

necessitate  recognizing  a  subspecies  typica  in  addition  to  the  making  of  a  new  com- 
bination. It  so  closely  simulates  A.  paiula  glabriuscula  in  most  of  its  characters  that 
its  intermediate  position  between  that  and  rosea  is  strongly  suggested. 

ECOLOGY  AND  USES. 

Atriplex  maritima  is  so  local  in  America  that  nothing  is  known  of  its  ecology  and 
uses. 

5.  ATRIPLEX  ROSEA  Linnaeus,  Sp.  PI.  ed.  2:1493,  1753.    Plate  38.    Redscale; 
Red  Orache. 

Erect  annual  herb,  1  to  20  dm.  high,  branched  from  the  base  to  form  rounded  bushy 
plants,  or  nearly  simple  and  strict  in  small,  starved  forms,  sometimes  simple-stemmed 
below,  but  with  divaricate  branches  above  the  middle;  branches  slender  or  stout, 
ascending,  commonly  a  little  angled,  nearly  glabrous,  stramineous,  the  bark  smooth  and 
persistent;  leaves  alternate,  except  the  lower,  either  sessile  or  petioled,  ovate  or  rhombic- 
ovate  to  lanceolate,  cuneate  or  rounded  at  base,  acute  or  rarely  somewhat  obtuse  at 
apex,  mucronulate,  2  to  6  cm.  long,  1  to  3  cm.  wide,  larger  in  occasional  plants  of  rapid 
growth,  remotely  sinuate-dentate  above  the  base  with  acute  or  obtuse  teeth,  thinly  or 
densely  furfuraceous,  usually  gray  or  whitish,  rarely  greenish,  soft  but  persistent  and 
becoming  cartilaginous  on  drying;  flowers  monoecious,  the  staminate  glomerules  in  the 
upper  axils  and  often  also  in  dense  terminal  spikes  1  cm.  or  less  long,  the  pistillate  also 
in  axillary  glomerules,  but  these  beneath  the  staminate,  many  of  the  intermediate 
glomerules  with  both  staminate  and  pistillate  flowers;  perianth  4-  or  5-lobed,  wanting 
in  the  pistillate  flowers ;  fruiting  bracts  sessile,  compressed,  united  usually  to  the  middle, 
rhombic  or  ovate  from  a  broad  base,  4  to  6  mm.  long,  of  about  the  same  width,  occa- 
sionally up  to  8  mm.  long  and  wide,  becoming  firm  and  strongly  indurated  in  age,  with 
wide  greenish  acutely  dentate  margins,  the  sides  usually  sharp-tuberculate,  3-nerved; 
seed  2  to  2.5  mm.  long,  dark  brown,  dull;  radicle  lateral. 

Introduced  and  now  abundant  in  all  of  the  western  United  States,  south  to  Chihuahua; 
also  at  various  places  along  the  Atlantic  seaboard  from  Massachusetts  to  Florida; 
native  and  widely  distributed  in  the  Old  World.  Type  locality,  Europe.  Collections: 
South  Boston  Flats,  Perkins,  according  to  Knowlton  and  Deane  (Rhodora  17:176, 
1915) ;  Albany,  New  York,  1867,  Peck  (Gr,  NY) :  Pensacola,  Florida,  Mohr  (US) ;  Shef- 
field, Missouri,  Bush  7058  (Gr,  NY,  US);  Laramie,  Wyoming,  Nelson  8961  (Gr,  NY, 
UC,  US);  Granger,  Wyoming,  Nelson  8I4O  (R,  types  of  A.  spatiosa  Nelson,  see  below); 
Murray,  Salt  Lake  County,  Utah,  W.  W.  Jones  374  (Gr);  Rio  Arriba  County,  New 
Mexico,  Standley  and  Bollman  10763  (US);  Juarez,  Chihuahua,  August  23,  1909,  Wooton 
(US);  Needles,  Mojave  Desert,  California,  Eastwood  5967  (SF);  Ballona,  near  Los 
Angeles,  California,  Braunton  687  (UC,  US) ;  Army  Street  Marsh,  San  Francisco,  Cali- 
fornia, September  9,  1918,  Eastwood  (SF);  Yreka,  northern  California,  Butler  1066 
(UC) ;  Reno,  Nevada,  Petersen  46^  and  ^65  (UC) ;  Yakima  County,  Washington,  Cotton 
889  (US);  Caiion  County,  Idaho,  Macbride  736  (Gr,  NY,  UC,  US).  Numerous  addi- 
tional localities  may  be  obtained  by  consulting  any  of  the  larger  herbaria. 

SYNONYM. 
1.  Atriplex  spatiosa  Nelson,  Bot.  Gaz.  34:. 360,  1902.     A.  rosea. 
RELATIONSHIPS. 

The  relationships  of  this  species  are  with  A.  maritima  and  A.  tatarica.  All  are  intro- 
ductions from  the  Old  World,  where  they  are  classed  as  belonging  to  the  section  Obio- 
nopsis,  or  Sclerocalymna  of  Ascherson,  best  characterized  by  the  hard  or  indurated  nature 
of  the  body  of  the  bracts  at  maturity.  The  foliage  of  rosea,  and  perhaps  also  of  the 
others,  likewise  becomes  hard  and  firm  at  maturity,  the  cartilaginous  leaves  persisting 
indefinitely  on  the  dead  and  pale  stems.     The  evolutionary  lines  between  these  species 


260  GENUS   ATRIPLEX. 

and  their  allies  of  the  Old  World  can  not  be  satisfactorily  worked  out  at  this  distance. 
It  may  be  suggested,  however,  that  because  of  its  evident  connection  with  A.  paiula 
glabriuscula,  A.  maritima  is  perhaps  the  most  primitive,  while  A.  tatarica  evidences  a 
higher  degree  of  specialization  than  the  others  in  the  much  more  thorough  separation 
of  the  two  sexes  in  the  inflorescence. 

Because  of  its  absence  from  all  but  the  more  recent  American  manuals,  Atriplex 
rosea  has  been  often  wrongly  identified.  The  inferior,  or  at  least  lateral  position  of  the 
radicle  is  often  overlooked  and  plants  are  then  especially  confused  with  A.  argeniea, 
A.  bracteosa,  and  A.  peniandra  arenaria.  It  may  be  distinguished  from  the  first  by  the 
narrower  leaves,  which  taper  to  the  base  and  are  more  sharply  dentate;  from  bracteosa 
it  differs  in  its  much  paler  foliage  and  in  the  absence  of  the  long,  moniliform  or  spike- 
Uke  staminate  inflorescences;  while  peniandra  arenaria  may  be  easily  recognized  by  the 
essentially  entire  and  usually  obtuse  leaves.  There  are,  of  course,  other  and  more 
constant  although  less  obvious  characters  upon  which  these  species  are  separated. 


Atriplex  rosea,  although  an  introduced  weed,  is  so  abundant  in  the  West,  especially 
in  the  arid  portions,  that  it  plays  an  ecological  role  of  great  importance.  It  is  most  char- 
acteristic of  roadsides,  fallow  fields,  and  waste  places,  where  it  is  often  the  pioneer 
consocies  of  the  subsere,  but  it  has  also  become  abundant  in  alkaline  valleys  and  plains, 
where  it  may  form  pure  consocies,  or  may  be  mixed  with  native  species  of  Atriplex  or 
other  halophytes.  It  is  exceedingly  variable  in  habit,  ranging  from  typically  branched 
forms  a  meter  or  more  high  to  giant  tumbleweeds  2  to  3  meters  tall  and  wide.  Under 
intense  competition  the  plants  are  slender  and  unbranched  and  in  extreme  conditions 
they  become  dwarfs  but  a  few  centimeters  in  height.  The  tumbleweed  habit  has 
doubtless  played  a  large  part  in  the  rapid  migration  of  this  species  throughout  the  West, 
as  it  also  explains  its  abundance  in  fenceways  and  roadsides.  Owing  to  its  size  and  abun- 
dance, this  is  one  of  the  most  important  host-plants  of  Euiettix  tenella,  the  leaf-hopper 
that  carries  the  curly-top  disease  of  the  sugar-beet.  In  the  West  the  plants  bloom 
from  July  through  September. 

USES. 

The  herbage  of  the  red  orache  has  many  uses  in  Europe,  but  none  of  them  are  of 
prime  importance.  Potash  is  obtained  from  it  in  Greece  and  it  is  utilized  to  a  limited 
extent  in  medicine  as  an  antiscorbutic  and  as  a  corrective  for  scrofula.  No  detailed 
study  of  the  forage  value  of  the  plant  has  been  made  in  America.  In  some  parts  of 
Nevada  the  young  plants  are  highly  prized  for  feeding  to  swine.  It  is  said  to  be  the 
cheapest  and  most  satisfactory  feed  there  available  for  fattening.  On  the  other  hand, 
recent  experiments  indicate  that  the  plants  are  mildly  poisonous  to  sheep  when  fed  in 
large  amount  and  to  the  exclusion  of  other  material.  An  analysis  is  given  by  Suarez 
y  Bermudez  (Exper.  Sta.  Rec.  33:466,  1915).  The  plants  grow  so  readily  in  the  western 
States  and  on  such  poor  soil  that  their  possible  utilization  for  stock-feeding,  both  direct 
and  as  silage,  should  be  thoroughly  tested. 

The  pollen  has  been  found  to  be  one  of  the  causes  of  hay-fever  of  the  late  summer 
type  in  the  West.  Preliminary  studies  indicate  that  all  species  of  the  genus  probably 
are  potential  causes  of  this  malady,  their  relative  importance  depending  more  upon 
the  abundance  in  which  the  plants  grow  in  the  populated  districts  than  upon  the  spe- 
cific properties  of  the  different  kinds.  It  does  not  follow,  however,  that  an  individual 
sensitive  to  one  species  is  necessarily  sensitive  to  all,  since  it  is  found  that  patients  react 
differently  to  pollen  of  the  various  species.  An  extract  of  the  pollen  is  used  in  making 
the  tests,  which  consist  of  intradermal  injections  of  extremely  dilute  solutions.     If  such 


A.    TATARICA.  261 

injection  results  in  a  definite  reddened  wheal,  the  conclusion  is  that  the  patient  is  super- 
sensitive to  that  particular  pollen  and  treatment  for  desensitization  is  then  begun  by 
making  injections  at  intervals  with  extracts  of  gradually  increasing  strength.  When 
no  further  reaction  is  obtained,  the  patient  is  assumed  to  be  immune  from  attacks  of 
hay-fever  from  the  species  used.  Although  some  people  are  sensitive  to  only  one  species 
of  pollen,  others  react  to  two  or  more,  in  which  case  it  is  necessary  to  treat  with  all  of 
these  if  perfect  immunity  is  sought. 

6.  ATRIPLEX  TATARICA  Linnaeus,  Sp.  PI.  105.3,  1753.     Plate  38. 

Erect  or  spreading  annual  herb,  2  to  15  dm.  or  more  high,  widely  branched  from  the 
base  to  form  tangled  masses  or  spreading  plants ;  branches  rather  stout,  obtusely  angled, 
nearly  glabrous,  stramineous,  the  bark  smooth  and  persistent;  leaves  alternate,  except 
probably  the  lower,  long-petioled  or  the  upper  nearly  sessile,  ovate  or  somewhat  triangu- 
lar, either  subhastate  or  cuneate  at  base,  acute  or  obtuse  at  apex,  3  to  6  cm.  long,  2  to  4 
cm.  wide,  deeply  or  shallowly  sinuate-dentate  or  only  undulate,  the  teeth  acute  or  obtuse, 
thinly  furfuraceous,  usually  greenish  at  least  on  the  upper  surface,  soft  and  thin;  flowers 
monoecious,  the  staminate  glomerules  in  slender  terminal  spikes  and  panicles  3  to  15 
cm.  long,  the  pistillate  fascicled  in  the  upper  leaf -axils;  perianth  5-cleft,  wanting  in  the 
pistillate  flowers;  fruiting  bracts  sessile,  moderately  compressed,  united  from  the  nar- 
rowed base  to  the  middle,  from  broadly  ovate  to  rhombic  or  nearly  flabelliform,  with 
wide  foliaceous  margins,  4  to  8  mm.  long,  3  to  7  mm.  wide,  hard  and  indurated  at 
maturity  except  for  the  broad  foliaceous  coarsely  dentate  margins,  the  sides  tuberculate 
or  smooth,  strongly  3-nerved  and  reticulate;  seed  1.5  to  2  mm.  long,  brownish;  radicle 
inferior,  ascending. 

Introduced  along  the  Atlantic  and  Gulf  coasts  from  Connecticut  to  Alabama;  widely 
distributed  in  the  Old  World.  Type  locality,  Siberia.  Collections:  Connecticut,  1908, 
Bissell  (Gr);  on  ballast,  northern  terminus  of  Eighth  Avenue,  New  York  City,  1879 
and  1880,  Brown  (Gr,  NY,  US);  on  ballast,  Greenwich  Point,  Philadelphia,  Penn- 
sylvania, 1874,  Parker  (Gr,  NY) ;  waste  ground,  Pensacola,  Florida,  Curtiss  6865  (NY) ; 
Mobile,  Alabama,  July  22,  1896,  Mohr  (Gr,  US). 

RELATIONSHIPS. 

The  hardened  fruiting  bracts  of  this  introduced  species  indicate  that  it  is  closely 
related  to  A.  rosea.  Its  best  distinguishing  character  is  the  wider  separation  of  the  two 
kinds  of  flowers,  the  staminate  being  assembled  into  elongated  terminal  spikes.  The 
leaves  are  thinner  than  in  rosea,  not  at  all  rigid,  and  are  commonly  subhastate  and  almost 
pinnatifid,  so  deep  are  the  lobes,  and  the  bracts  are  more  nearly  triangular  because  of  the 
strong  lateral  angles.  The  introduced  American  plants,  as  far  as  seen,  are  fairly  uniform 
in  these  characters.  In  the  Old  World  is  found  a  large  series  of  forms,  many  of  which 
have  been  named  and  described.  These  are  based  upon  habit,  color,  shape  of  leaf, 
margins  of  bracts,  and  similar  features.  Twenty-one  are  described  in  Ascherson  and 
Graebner's  Synopsis  of  the  Middle  European  Flora. 

The  misdetermination  of  certain  collections  of  A.  tatarica  from  the  Southern  States 
has  led  to  the  erroneous  inclusion  of  A.  lampa  Gillies,  a  South  American  species,  in 
the  North  American  flora.  The  collections  so  referred  are:  Pensacola,  Florida,  Curtiss 
6865,  and  Mobile,  Alabama,  July  22,  1896,  Mohr.  These  specimens  have  monoecious 
flowers,  the  staminate  in  elongated  spikes,  the  pistillate  with  triangular  very  acute 
bracts,  while  A.  lampa  is  a  shrub  with  dioecious  flowers,  the  staminate  in  short 
rounded  clusters,  the  pistillate  with  orbicular,  very  obtuse  bracts. 
ECOLOGY  AND  USES. 

As  an  introduced  ballast-plant  of  rare  occurrence,  Atriplex  tatarica  is  unimportant, 
both  ecologically  and  economically. 


262  GENUS   ATRIPLEX. 

7.  ATRIPLEX  SEMIBACCATA  Brown,  Prodr.  406,  1810.     Plate  39.     Fleshscale; 
Australian  Saltbush. 

Prostrate  perennial  herb,  becoming  woody  at  base,  the  trailing  stems  sometimes  as 
much  as  15  dm.  long;  branches  wiry,  not  angled,  at  first  mealy,  soon  glabrate  and  then 
stramineous,  the  bark  rough  only  on  very  old  basal  portions;  leaves  alternate,  numerous, 
short-petioled,  elliptic  or  elliptic-oblong,  sometimes  slightly  spatulate,  narrowed  at  base, 
acute  or  obtuse  at  apex,  1.5  to  3  or  4  cm.  long,  0.3  to  1.2  cm.  wide,  irregularly  and  remotely 
repand-dentate  or  many  entire,  comparatively  thin,  gray  with  a  fine  dense  scurf,  or  this 
thinner  and  the  leaves  then  greenish  especially  on  the  upper  surface,  strongly  1-nerved 
from  the  base;  flowers  monoecious,  the  staminate  in  small  terminal  leafy-bracted  glo- 
merules,  the  pistillate  solitary  or  in  few-flowered  clusters  in  the  axils  of  nearly  all  but  the 
uppermost  leaves;  perianth  either  4-  or  5-cleft  in  the  staminate  flowers,  wanting  in  the 
pistillate;  fruiting  bracts  sessile  or  on  short  stalks,  convex  and  fleshy  when  fresh  but 
compressed  and  nearly  flat  when  dry,  rhombic,  3  to  6  mm.  long,  3  to  5  mm.  broad  across 
the  middle,  cuneate  at  base,  acute  at  apex,  united  only  below  the  middle,  the  margins 
denticulate  or  entire,  the  sides  not  appendaged  but  strongly  3-  or  5-nerved  (the  nerves 
especially  prominent  when  dry),  fleshy-thickened  and  turning  red  in  living  plants;  seeds 
of  two  kinds,  one  nearly  black  and  only  1.5  mm.  long,  the  other  brown,  about  2  mm.  long, 
more  convex,  and  with  a  groove  near  the  margin;  radicle  lateral. 

Native  of  Australia;  introduced  and  naturalized  in  California,  Arizona,  and  southern 
New  Mexico ;  especially  abundant  in  alkaline  soil  in  the  San  Joaquin  and  Imperial  Val- 
leys and  the  coastal  slope  of  southern  California.  Type  locality,  vicinity  of  Port  Jackson, 
Australia.  Collections,  all  from  CaUfornia,  except  as  otherwise  indicated:  Rough  and 
Ready  Island,  San  Joaquin  County,  Berg  28  (UC) ;  Marin  County,  in  a  salt  marsh,  Au- 
gust, 1900,  Eastwood  (UC);  near  Bakersfield,  October  23,  1919,  Hall  (CI);  roadside  near 
Ballona  Lagoon,  Los  Angeles  County,  Chandler  2020  (UC);  Gardena,  Los  Angeles 
County,  Braunton  623  (UC) ;  Avalon,  Santa  Catalina  Island,  Millspaugh  4603  (UC) ;  near 
Rincon,  Riverside  County,  Reed  374  (UC) ;  La  JoUa,  Millspaugh  4467  (UC) ;  mesa  near 
Otay,  San  Diego  County,  Abrams  3622  (UC);  Tucson,  Arizona,  Jones  (Herb.  Jones); 
Mesilla  Valley,  New  Mexico  (R);  Alamogordo,  New  Mexico,  according  to  Standley 
(Contr.  U.  S.  Nat.  Herb.  19:204,  1915). 

SYNONYM. 

1.  Atriplex  flagellaris  Wooton  and  Standley,  Contr.  U.  S.  Nat.  Herb.  16:119,  1913.— Reduced  to  A. 
semibaccata  by  the  authors  of  the  proposed  species  (Contr.  U.  S.  Nat.  Herb.  19:204,  1915). 
RELATIONSHIPS. 

This  is  an  Australian  species  the  relationships  of  which  have  not  been  determined. 
The  lateral  position  of  the  radicle  and  the  nearly  distinct  fruiting  bracts  suggest  that  it 
is  one  of  the  more  primitive  forms. 

ECOLOGY. 

Although  an  introduced  species,  Atriplex  semibaccata  is  now  so  thoroughly  at  home  in 
California  that  it  plays  the  ecological  role  of  a  native.  Its  habit  of  forming  large  spread- 
ing mats  makes  it  an  effective  binder  of  sand  and  other  bare  soils,  and  hence  it  is  a 
characteristic  dominant  of  back-strands,  sandy  fields,  and  clay  slopes,  in  the  coast  region 
especially.  Its  halophytic  nature  is  indicated  by  nearly  pure  communities  in  saline  flats 
and  on  sea-cliffs,  where  it  is  also  often  associated  with  A.  lenliformis  breweri  and  species 
of  Suaeda.  Owing  to  the  protection  it  affords  against  erosion,  this  species  regularly 
occurs  as  a  rehct  along  the  eroding  rim  of  bad  lands  of  the  Fernando  formation,  and  is 
typical  of  the  initial  stages  of  such  areas.  It  readily  finds  its  way  into  roadsides,  fallow 
fields,  and  other  disturbed  places,  and  it  persists  in  annual  grassland,  where  the  dense 
mats  are  able  to  make  headway  in  the  competition  with  wild  oats  and  the  brome-grasses. 


A.    SEMIBACCATA — A.    HALIMOIDES.  263 

USES. 

This  species  was  introduced  into  America  by  the  California  Experiment  Station  in 
1888  as  a  forage  and  hay  plant  for  alkaline  districts.  Its  cultivation  was  extended  to  all 
of  the  warmer  parts  of  the  State  as  rapidly  as  seed  became  available,  and  for  more  than 
a  decade  it  was  in  high  favor  with  stockmen,  since  it  grew  readily  on  land  too  poor  for 
other  crops.  Although  now  much  less  highly  prized,  it  is  still  useful  as  an  adjunct  to 
other  browse  and  forage  plants,  especially  for  the  purpose  of  carrying  stock  through  unfa- 
vorable seasons.  When  other  feed  is  plentiful,  most  animals  avoid  the  Australian 
saltbush,  as  it  is  commonly  known.  Aside  from  its  forage  value  for  hogs,  sheep,  cattle, 
and  horses,  the  foliage  and  seeds  are  eaten  by  poultry.  In  establishing  the  plant,  the 
best  results  are  obtained  by  first  plowing  and  harrowing  the  land,  after  which  the  seed 
is  sown  broadcast  or  drilled,  preferably  just  before  a  rain.  The  seed  is  regularly  carried 
in  stock  by  California  seedsmen.  The  plants  are  killed  by  temperatures  of  about  14°  F. 
and  therefore  can  not  be  grown  in  cold  regions.  Further  details  and  analyses  are  given 
in  the  reports  and  bulletins  of  the  California  Experiment  Station  (see  especially  Bull. 
125, 1899).  Analyses  are  given  also  by  Headden  (Colo.  Exp.  Sta.  Bull,  135,  1908),  who 
concludes  with  the  following  statement  of  facts,  which  he  considers  to  have  been  estab- 
lished for  this  plant : 

"First,  when  once  established  it  will  endure  drought  and  even  make  a  good  crop  with  less  than  5  in.  of  rain- 
fall. Second,  that  stock  will  eat  it  or  readily  learn  to  eat  it  either  green  or  as  hay.  Third,  that  it  will  produce 
very  heavily  under  favorable  conditions.  Fourth,  that  it  will,  when  fed  alone,  maintain  the  animals,  and  even 
better  results  are  claimed  for  it.  Fifth,  that  the  hay  is  rich  in  protein,  as  rich  or  even  richer  than  alfalfa. 
Sixth,  that  its  coefficients  of  digestion  are  excellent,  except  for  the  fat  or  ether  extract  and  crude  fiber.  Seventh, 
that  it  has  no  injurious  effects  on  the  animals  even  when  they  have  no  other  fodder  with  it.  The  following 
facts,  however,  remain,  that  it  has  not  become  popular,  and  that  when  fed  alone  it  does  not  produce  the  results 
that  its  composition  and  coefficients  of  digestion  would  seem  to  warrant  us  in  expecting." 

The  most  recent  bulletin  dealing  with  the  culture  and  uses  of  this  species  in  North 
America  is  one  by  McKee  (U.  S.  Dept.  Agr.  Bull.  617,  1919). 

The  Australian  saltbush  is  of  economic  interest  also  as  a  host  plant  for  Eutettix  tenella, 
the  insect  that  carries  the  disease  of  the  sugar-beet  known  as  curly-top  (see  under  A. 
bracteosa,  p.  307).  It  is  especially  important  in  the  Imperial  Valley,  California,  where 
it  serves  to  carry  the  insect  over  the  autumn.  Other  autumn  host  plants  are  here  almost 
wanting,  so  that  if  it  were  not  for  this  Atriplex,  the  Eutettix  would  be  much  less  plentiful 
or  perhaps  not  able  to  persist. 

8.  ATRIPLEX  HALIMOIDES  Lindley,  in  Mitchell,  Three  Exped.  East.  Austral.  1:285,  1838. 

Plate  39. 

Erect  spreading  or  procumbent  perennial  subshrub  or  herb,  1.5  to  4  dm.  high;  branches 
brittle,  not  angled,  at  first  slightly  white-mealy  but  soon  glabrate  and  pale;  leaves  alter- 
nate, crowded,  petioled,  oblanceolate  to  rhomboid  with  a  much  narrowed  base,  acute  at 
apex,  1  to  3  cm.  long,  0.3  to  1.5  cm.  wide,  remotely  repand-dentate  or  some  entire,  rather 
thin,  white  with  a  fine  dense  mealy  scurf  or  less  scurfy  and  greenish,  1 -nerved;  flowers 
monoecious,  the  staminate  in  short  spikes  in  the  upper  axils,  the  pistillate  solitary  or  in 
few-flowered  clusters  in  the  axils  below;  perianth  5-cleft  in  the  staminate  flowers,  wanting 
in  the  pistillate;  fruiting  bracts  sessile,  not  compressed  but  loose  and  spongy,  the  open 
tissue  held  together  by  strong  web-like  fibers,  broadly  turbinate  or  nearly  hemispheric 
with  a  much  depressed  or  flattened  summit  (apparently  globoid  in  some  pressed  speci- 
mens), 6  to  12  mm.  in  diameter,  united  except  at  the  minute  valve-like  apical  tips, 
sparsely  scurfy;  seeds  of  2  sorts,  one  kind  1.5  mm.  long  and  dark  reddish-brown,  the  other 
slightly  smaller  and  black ;  radicle  inferior. 

Introduced  from  Australia;  incompletely  naturalized  in  southern  California.  Type 
locality,  eastern  Australia.  Collections:  Cockatoo  Ranch,  near  El  Nido,  San  Diego 
County,  California,  Abrams  3527  (DS,  Gr,  NY,  UC,  US). 


264  GENUS   ATRIPLEX. 

SYNONYM. 
1.  Atriplex  lindleyi  Moquin,  in  DeCandoUe,  Prodr.  13':  100,  1849.— This  name  was  given  to  the  present 
species  because  of  the  earlier  A.  halimoides  Tineo,  which,  however,  has  never  been  otherwise  pubHshed  than  as 
a  name  in  a  garden  catalogue  (according  to  Bentham,  Fl.  Austral.  5: 179,  1870).     There  is  also  an  A.  halimoides 
Rafinesque  (Amer.  Mo.  Mag.  2: 176,  1818),  but  this  is  universally  regarded  as  the  same  as  A.  patida  hastata. 

RELATIONSHIPS. 
This  is  not  related  to  any  American  species.  It  differs  from  all  native  Atriplexes  in 
the  highly  spongious  bracts.  This  peculiar  development  is  characteristic  of  several 
other  Australian  species,  notably  A.  holocarpa  and  A.  vesicaria.  Both  of  these  have 
been  grown  in  American  gardens  with  the  thought  of  using  them  as  forage  plants,  but 
neither  has  been  found  suitable  for  general  planting. 

ECOLOGY  AND  USES. 

Atriplex  halimoides  is  a  native  of  the  deserts  of  Australia,  where  it  grows  under  ex- 
tremely xerophytic  conditions.  It  was  introduced  into  California  about  1885  and  at 
first  seemed  to  give  much  promise  as  a  browse  plant  for  alkaline  districts.  Seeds  formed 
within  a  few  months  after  sowing  and  when  the  plants  were  cut  or  pastured  down  a 
compact  mass  of  soft  new  growth  was  formed  (according  to  Wickson,  Calif.  Agr.  Exp. 
Sta.  Rep.  for  1897-8:244,  1900).  But  this  species  did  not  become  popular  with 
farmers.  The  garden  experiments  were  made  mostly  at  Berkeley  and  in  the  Sacramento 
and  San  Joaquin  Valleys,  but  the  only  known  locality  where  A.  halimoides  escaped  to 
wild  conditions  is  in  San  Diego  County.  Chemical  analyses  of  cultivated  plants  are 
reported  by  Shepard,  Saunders,  and  Knox  (S.  Dak.  Agr.  Exp.  Sta.  Bull.  69:42,  1901) 
and  by  Knight,  Heppner,  and  Nelson  (Wyo.  Agr.  Exp.  Sta.  Bull.  65:50,  1905). 

9.  ATRIPLEX  DIOECA  (Nuttall)  Macbride,    Contr.  Gray  Herb.  n.  s.  53:11,  1918.     Plate  40. 

RiLLSCALE. 

Erect  or  spreading  annual  herb,  1  to  3  dm.  high,  branched  from  the  base  to  form 
rounded  plants  usually  1  to  3  dm.  broad,  the  twigs  erect ;  branches  rather  stout,  smooth, 
lightly  furfuraceous  when  young  but  soon  glabrous  and  dull  green,  the  old  bark  whitish; 
leaves  alternate,  sessile,  lanceolate  or  lance-ovate,  either  rounded  or  tapering  to  the 
base,  acute  or  subacuminate  at  apex,  1  to  2.5  cm.  long,  0.2  to  0.8  cm.  wide  (rarely  up 
to  3.5  cm.  long  and  1  cm.  wide),  the  upper  ones  moderately  smaller,  the  margins  entire, 
thickish  and  succulent,  sparsely  farinose  when  young,  but  soon  glabrous  and  glaucous; 
flowers  monoecious,  the  staminate  in  small  glomerules  which  are  widely  separated  in 
nearly  naked  terminal  spikes  and  also  in  the  upper  leaf-axils,  the  pistillate  solitary  or 
few  in  the  axils  of  the  middle  leaves,  the  two  sexes  mixing  in  some  of  the  axils;  perianth 
of  staminate  flowers  cup-shaped,  cleft  into  4  or  5  lobes  each  with  a  fleshy  crest  on  the 
back,  of  pistillate  flowers  minute,  the  3  or  4  sepals  distinct  to  the  base;  fruiting  bracts 
sessile  by  a  narrow  base,  compressed,  united  to  the  apex,  ovate,  about  2  mm.  long,  1.5 
mm.  wide,  herbaceous,  not  margined,  the  faces  not  appendaged  but  rough  with  a  coarse 
scurf;  seed  1.5  mm.  long;  radicle  superior.     {Kochia  dioeca  Nuttall,  Genera  1:200,  1818.) 

Alberta  and  Saskatchewan  to  western  Nebraska,  Wyoming,  and  Montana;  the 
Nebraska  plants  were  probably  introduced,  the  seed  having  been  brought  in  by  stock 
cars,  according  to  Bates  (Asa  Gray  Bull.  6:35-37,  1898).  Type  locality,  near  Fort 
Mandan,  North  Dakota.  Collections:  Rosedale  Trail,  Alberta,  Moodie  1116  (DS,  Gr, 
NY,  US);  southern  Saskatchewan,  Macoun  1501  (US);  Glen  Allen,  North  Dakota, 
Holzinger  30  (US) ;  Owl  Butte,  South  Dakota,  Griffiths  338  (US) ;  Pennington  County, 
South  Dakota,  Over  1808  (US);  Cretaceous  hills  below  Fort  Pierre,  Nebraska  Territory, 
June,  1853-54,  Hayden  (NY);  South  Fork  Powder  River,  Johnson  County,  Wyoming, 
Goodding  25^  (DS,  Gr,  R,  NY,  UC,  US) ;  north  of  Baggs,  Carbon  County,  Wyoming, 


A,    DIOECA — A.    MONILIFERA.  265 

Osterhout  2637  (NY);  Rock  Creek  Station,  Wyoming,  August  26,  1881,  Ward  (US); 
Teton  River  country,  Montana,  Scribner  225  (Gr).  Additional  localities  represented  by 
specimens  at  the  Rocky  Mountain  Herbarium  include  Wallace  Creek  and  Sweetwater, 
Wyoming,  northwestern  Harding  County,  North  Dakota,  and  Falls  River  County, 
South  Dakota. 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Atriplex  endolepis  Watson,  Proc.  Am.  Acad.  9: 110,  1874. — The  same  as  A.  dioeca. 

2.  A.  ovATA  Clements  and  Clements,  Rocky  Mts.  Fls.,  61,  1917. — ^1  dioeca. 

3.  A.  sucKLEYANA  Rydberg,  Mem.  N.  Y.  Bot.  Gard.  1 :  134, 1900. — This  combination  was  proposed  to  avoid  a 
conflict  with  A.  dioeca  Rafinesque  (Am.  Mo.  Mag.  2: 176,  1818).  However,  this  latter  was  only  incidentally 
mentioned  by  Rafinesque.  In  any  event  it  would  not  interfere  with  the  use  of  the  name  dioeca 
by  those  following  the  International  Code,  since  Rafinesque  had  in  mind  a  minor  form  of  A.  patula.  A.  suckley- 
ana  Watson,  1.  c,  1 1 1 ,  1874,  is  an  entirely  different  plant,  now  referred  to  the  genus  Suckleya. 

4.  Endolepis  dioeca  Standley,  N.  Am.  Fl.  21:73,  1916. — A.  dioeca. 

5.  E.  OVATA  Rydberg,  Bull.  Torr.  Club  30:248,  1903.— The  form  with  ovate  3-nerved  leaves  usually 
less  than  1  cm.  long.  Type  locality,  Buifalo,  Wyoming.  The  Ward  specimen  cited  above  belongs  here,  as  also 
Goodding's  254.  In  the  latter  the  leaves  are  1  to  2  cm.  long,  mostly  3-  or  5-nerved  at  the  base,  but  some  only 
l-nerved,  and  is  therefore  somewhat  intermediate  to  typical  dioeca. 

6.  E.  sucKLEYi  Torrey,  in  Gray,  Pacif.  R.  R.  Rep.  12=: 47,  plate  3,  I860.— Exactly  the  same  as  A.  dioeca,  as 
indicated  by  the  description  and  the  excellent  plate. 

7.  KocHiA  DIOECA  Nuttall,  Genera  1 :200,  1818. — The  first  description  of  the  species. 

8.  Salsola  dioeca  Sprengel,  Syst.  Veg.  1 : 923, 1825. — A.  dioeca. 

RELATIONSHIPS. 

The  primitive  position  of  A.  dioeca  is  indicated  by  the  presence  of  a  well-formed 
perianth  in  the  pistillate  flowers.  This  perianth  consists  of  3  or  4  scales  about  as  long 
as  the  ovary  and  apparently  is  never  wanting.  Because  of  its  presence  and  the  unusual 
shape  of  the  calyx  in  the  staminate  flowers,  Torrey,  Standley,  and  others  would  make 
this  species  the  type  of  a  distinct  genus,  namely,  Endolepis.  The  unreliability  of  the 
character  of  the  perianth  scales  is  seen  in  the  related  A.  phyllostegia,  where  they  may 
be  either  present  or  wanting,  as  will  be  more  fully  indicated  under  that  species.  These 
two  and  A.  monolifera  constitute  a  small  group  of  succulent  annuals  of  western  North 
America.  They  are  well  separated  geographically  from  one  another  and  none  of  them 
is  at  all  abundant. 

ECOLOGY  AND  USES. 

Atriplex  dioeca  is  a  characteristic  pioneer  in  the  bad  lands  of  the  West.  Usually  it 
occurs  as  small  families  in  rillways  or  on  tiny  alluvial  fans,  but  it  is  also  associated  with 
species  of  Eriogonum  or  Atriplex  to  form  open  colonies.  Less  commonly  it  makes  a 
carpet  of  considerable  extent  on  alkaline  soils  derived  from  the  Mancos  and  other 
shales.  The  plants  bloom  from  midsummer  to  fall.  This  species  is  usually  too  sparse 
and  low  to  be  of  value  even  for  grazing. 

10.  ATRIPLEX  MONILIFERA  Watson,  Proc.  Am.  Acad.  9:111,  1874.     Plate  40. 

Spreading  annual  herb,  the  size  not  known  but  probably  small,  branched  from  the 
base,  the  twigs  decumbent  or  ascending;  branches  leafy,  hoary-farinose,  doubtless 
glabrate;  leaves  alternate,  sessile,  broadly  elliptic  or  broadly  ovate,  0.5  to  1.5  cm.  long, 
0.3  to  1  cm.  wide,  the  upper  ones  scarcely  reduced,  broad  at  the  base,  obtuse  or  some- 
times acute  at  apex,  the  margins  entire  or  somewhat  repand-dentate,  thickish,  densely 
gray-farinose;  flowers  monoecious,  the  staminate  in  approximate  glomerules  forming 
terminal  moniliform  naked  spikes,  the  pistillate  flowers  solitary  in  the  leaf-axils;  perianth 
of  staminate  flowers  5-cleft  to  the  middle,  each  lobe  with  a  thickened  ridge  down  the 
back,  of  pistillate  flowers  described  as  consisting  of  2  minute  scales  alternating  with 


266  GENUS   ATRIPLEX. 

the  bracts;  fruiting  bracts  and  seeds  probably  as  in  yl.  dioeca  but  not  known  in  mature 
condition. 

Known  only  from  the  original  collection  from  the  dried  bed  of  a  lake  in  Bolson  de 
Mapimi,  Chihuahua,  April  13,  1847,  Gregg  (Gr). 

SYNONYM. 
This  species  has  been  transferred  to  Endolepis,  taking  there  the  name  E.  monilifera  Standley  (N.  Am.  Fl. 
21:73,1916). 

RELATIONSHIPS. 

This  species  is  so  close  to  A.  dioeca  that  on  the  basis  of  known  characters  the  two 
might  almost  be  united.  It  differs  principally  in  the  proportionately  wider  leaves,  the 
dense  staminate  spikes,  the  more  open  and  spreading  perianth  of  the  staminate  flowers, 
and  the  densely  mealy  foliage.  The  wide  geographic  separation  of  the  two  suggests  that 
further  differences  may  be  found  when  more  abundant  and  fully  mature  material  is 
available  for  study.  The  status  of  the  genus  Endolepis,  to  which  this  species  has  been 
referred,  has  been  mentioned  under  A.  dioeca. 

ECOLOGY  AND  USES. 

Nothing  is  known  of  the  ecology  and  uses  of  this  species. 

11.  ATRIPLEX  PHYLLOSTEGIA  (Torrey)  Watson,  Proc.  Am.  Acad.  9: 108,  1874.     Plate  40. 
Arrowscale. 

Erect  annual  herb,  1  to  4  dm.  high,  branched  throughout  to  form  a  rounded  or  pyram- 
idal bushy  plant,  in  some  cases  less  widely  branched  and  the  plant  then  narrow  and 
nearly  columnar;  branches  slender,  nearly  terete,  faintly  striate,  sparsely  furfuraceous  or 
glabrate,  the  pale  bark  persistent;  leaves  all  alternate  except  one  or  two  lower  pairs, 
petioled  or  sessile,  rhombic-triangular  or  hastate  to  broadly  ovate  or  lanceolate,  the  ter- 
minal portion  commonly  elongate-lanceolate  and  acute  or  acuminate,  obtuse  or  cuneate  at 
base,  1  to  4  cm.  long,  1  to  3  cm.  wide,  entire,  thick  and  succulent  when  fresh,  green, 
sparsely  furfuraceous  but  glabrate,  chartaceous  when  dry;  flowers  monoecious  or  the 
plants  wholly  pistillate,  the  staminate  in  small  axillary  glomerules  near  the  ends  of  the 
branches,  the  pistillate  clustered  in  all  of  the  axils  except  the  upper  when  these  bear 
staminate  flowers;  perianth  5-cleft  in  the  staminate  flowers,  sometimes  present  in  pis- 
tillate flowers  and  then  consisting  of  1  to  4  scales  as  long  as  the  seed  or  often  much 
shorter;  fruiting  bracts  sessile  or  subsessile  or  sometimes  on  stalks  up  to  15  mm.  long, 
compressed,  united  only  near  the  base,  lanceolate  or  lance-oblong,  often  from  a  hastate 
cordate  or  winged  base,  the  free  tips  attenuate  and  widely  separated,  5  to  20  mm.  long, 
3  to  5  mm.  wide  at  base,  entire  or  deeply  laciniate,  the  sides  smooth,  except  for  the  3 
prominent  ribs  and  cross-veinlets,  or  variously  appendaged,  the  appendages  sometimes 
linear  and  up  to  4  mm.  long;  seed  1.2  mm.  long,  brown;  radicle  superior.  {Obione 
phyllostegia  Torrey  in  Watson,  Botany  King's  Expl.  291,  1874). 

Sandy  soil,  western  Utah,  Nevada,  southeastern  Oregon,  and  eastern  California, 
extending  across  Tehachapi  Pass  and  northward  in  the  San  Joaquin  Valley  nearly  to 
Tracy.  Type  locality,  between  the  Truckee  and  Humboldt  Rivers,  western  Nevada. 
Collections:  Gate  of  Gibraltar,  Utah,  June  3,  Engelmann  (NY) ;  Dairy,  Klamath  County, 
Oregon,  alkali  basin,  Applegate  452  (Gr);  Margin  of  Silver  Lake,  Lake  County,  Oregon, 
Cusick  2787  (Gr,  UC);  Steamboat  Springs,  Nevada,  Lemmon  II42  (Gr);  Truckee  Pass 
and  Hot  Spring  Mountains,  Nevada,  Watson  986  (Gr,  types) ;  Wadsworth,  near  Clarks, 
Nevada,  June  15, 1897,  Jones  (Herb.  Jones,  type  of  A.  draconis  Jones,  minor  variation  2) ; 
California:  near  Keeler,  Inyo  County,  Coville  and  Funston  875  (US,  type  of  Endolepis 
covillei  Standley,  minor  variation  3);  Antelope  Valley,  Davy  2196  (UC);  Kern  Lake, 
San  Joaquin  Valley,  Davy  21S9  (UC);  Chowchilla,  Madera  County,  Hall  11788  (UC). 
Additional  localities  are  cited  in  table  25. 


A.    PHYLLOSTEGIA. 


267 


MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Atriplex  covillei  Macbride,  Contr.  Gray  Herb.  N.  S.  53:11,  1918. — Based  upon  Endolepis  covillei, 
which  see  in  this  list. 

2.  A.  DHACONis  Jones,  Contr.  West.  Bot.  8:40,  1898. — Characterized  by  an  exceptional  development  of  the 
basal  lobes  of  the  fruiting  bracts.  These  lobes  are  wing-like  and  more  or  less  laciniate,  sometimes  also  with 
green  ridges  or  teeth  along  their  sides  which  "give  the  fruit  a  fantastic  appearance,  of  halberd  shape."  These 
characters  are  exceedingly  variable  even  on  individual  plants.  In  the  type  specimens  many  of  the  bracts  have 
developed  neither  wings  nor  appendages,  but  are  entirely  smooth  and  narrowed  to  the  base.  The  type  of  draconis 
was  described  as  dioecious  and  the  specimens  exhibit  a  strong  tendency  to  dioecism,  but  they  are  not  purely  so, 
the  pistillate  plants  having  a  few  staminate  flowers,  while  at  least  some  of  the  staminate  plants  are  well  supplied 
with  pistillate  flowers.  The  bracts  of  these  latter,  however,  are  only  2  to  4  mm.  long  and  either  arrested  in 
their  development  or  immature.  The  types  came  from  between  Wadsworth  and  Clarks,  western  Nevada, 
according  to  Professor  Jones,  the  collector,  who  has  himself  made  the  reduction  of  his  species  to  phyllostegia 
(Jones,  Contr.  West.  Bot.  11:20,  1903). 

3.  Endolepis  covillei  Standley,  N.  Am.  Fl.  21 :  73,  1916.— The  same  as  A.  phyllostegia.  Based  upon  plants 
in  which  a  few  scales,  representing  a  reduced  perianth,  were  found  between  the  bracts  of  the  pistillate  flowers. 
Fully  discussed  under  Relationships. 

4.  E.  PHYLLOSTEGIA  Rydberg,  Bull.  Torr.  Club  39:312,  1912.— Based  upon  Obione  phyllostegia  Torrey  (No. 
5  of  this  list).     Transferred  because  of  the  presence  of  a  perianth  in  some  pistillate  flowers. 

5.  Obione  phyllostegia  Torrey,  in  Watson,  Botany  King's  Expl.  291,  1874. — The  original  name  for  A. 
phyllostegia. 

RELATIONSHIPS. 

There  is  little  doubt  that  Atriplex  phyllostegia  is  very  closely  related  to  A.  dioeca.  It 
may,  in  fact,  be  a  direct  development  from  this,  as  is  suggested  by  the  frequent  appear- 
ance of  perianth  scales  in  the  pistillate  flowers.  These  structures  are  only  vestiges, 
apparently,  even  in  dioeca,  and  phyllostegia  may  therefore  be  taken  as  the  more  advanced 
type,  since  they  are  sometimes  present  and  sometimes  entirely  suppressed.  The  present 
species  is  the  more  highly  specialized,  as  is  shown  by  the  remarkable  development  of 
unique  features  of  the  leaves  and  bracts,  a  notable  tendency  toward  dioecism,  and  cer- 
tain other  details.  (The  other  species  is  strictly  monoecious,  notwithstanding  its 
name.)  While  A.  phyllostegia  is  much  like  some  forms  of  the  argentea  group  in  technical 
characters,  there  is  no  evidence  that  it  was  the  starting  point  of  these.  The  develop- 
ment of  unusual  features,  especially  the  arrow-like  foliage,  indicates  rather  that  it  is  the 
terminus  of  a  short  lateral  branch  of  the  evolutionary  tree. 

Perhaps  nowhere  in  the  three  genera  here  treated  is  there  a  better  example  of  the 
futility  of  attempts  to  establish  and  maintain  genera  on  trivial  characters  than  is  fur- 
nished by  the  so-called  genus  Endolepis,  to  which  a  part  of  A.  phyllostegia  recently  has 
been  transferred.  The  unnecessary  increase  in  synonymy  and  the  resulting  confusion 
which  results  from  the  incomplete  examination  of  material  is  likewise  well  illustrated  here. 
All  of  the  opinions  now  to  be  cited  are  those  of  leading  systematists.  The  differences  in 
opinion  and  treatment  may  be  taken,  therefore,  as  an  index  of  the  efficiency  of  taxonomic 
methods,  although  it  should  be  noted  that  the  earlier  workers  were  handicapped  by  a 
lack  of  abundant  material. 

Endolepis  was  first  proposed  as  a  genus  by  Torrey  (in  Gray,  Pacif.  R.  R.  Rep.  12^:47, 
1860),  with  E.  suckleyi  as  the  only  species.  This  is  exactly  the  same  as  Kochia  dioeca 
Nuttall,  or  Atriplex  dioeca,  as  it  is  now  called,  the  earlier  Nuttallian  name  having  been 
apparently  overlooked.  Torrey  characterized  his  genus  especially  by  "the  remarkable 
calyx  of  the  staminate  flowers,  and  by  the  presence  of  a  manifest  3-sepalous  calyx  in  the 
fertile  flowers."  The  feature  of  the  staminate  calyx  still  holds  for  dioeca  and  its  close 
associate,  monilifera.  But  the  presence  of  a  calyx  in  the  pistillate  flowers  is  of  value  as 
a  character  only  as  it  furnishes  a  clue  to  relationships  and  shows  how  closely  Endolepis 
is  connected  with  Atriplex.  The  evidence  of  this  is  found  in  A.  phyllostegia,  described  by 
Torrey  14  years  after  he  established  Endolepis.  No  calyx  was  found  in  the  pistillate 
flowers  at  the  time,  but  it  is  now  well  known  that  the  calyx,  which  consists  of  a  few 


268 


GENUS   ATRIPLEX. 


minute  scales,  may  be  either  present  or  absent.  These  scale  structures,  or  sepals,  were 
first  noted  by  Watson  (Proc.  Am.  Acad.  9:108,  1874),  who  thereupon  promptly  reduced 
Endolepis  to  Atriplex  (1.  c,  110). 

When  Standley  reached  this  group  in  his  revision  for  the  North  American  Flora,  he 
attempted  to  sustain  Endolepis  on  the  basis  of  the  perianth  in  the  pistillate  flowers,  and 
he  did  this  by  the  daring  method  of  spUtting  phyllostegia  into  two  species,  assigning  those 
plants  without  the  perianth  to  Atriplex  phyllostegia,  while  those  with  perianth  were 
referred  to  his  new  Endolepis  covillei,  a  species  especially  set  up  to  receive  them.  An 
inconsistency  resulting  from  this  treatment  was  noted  by  Macbride  (Contr.  Gray  Herb. 
N.  S.  53: 11,  1918),  who  pointed  out  that  in  the  type  species  of  Atriplex  {A.  hortensis)  some 
of  the  pistillate  flowers  have  a  regular  perianth,  as  called  for  in  all  modern  descriptions, 
including  that  of  Standley.     Macbride  then  accepted  covillei  as  a  species  and  transferred 


-Laaves  of  Atriplex  phyllostegia  to  illustrate  variation  in  shape  of  blade  and  length  of  petiole;  also  to  show  lack  of 
concomitance  with  flower  characters:  a,  b,  c,  leaves  from  the  type  of  the  form  called  A.  covillei,  perianth  present 
in  pistillate  flowers  of  this  plant;  d.  e,  f,  g,  leaves  from  the  type  of  the  form  called  .4.  draconis,  perianth  wanting 
in  pistillate  flowers;  A,  i,  leaves  as  in  genuine  A.  phyllostegia  (Reno,  Nevada,  Curran,  185923  UC),  perianth 
n  A.  covillei.     All  X  0.8. 


it  to  Atriplex,  apparently  without  investigating  the  value  of  the  character  upon  which 
it  was  based.  As  a  result  of  the  present  study,  covillei  is  found  to  be  entirely  devoid  of 
substantiating  characters  and  it  can  not  be  retained  even  in  the  most  subordinate  rank. 
An  examination  of  the  material  in  several  herbaria  shows  conclusively  that  the  perianth 
scales  may  be  either  present  or  absent,  even  on  a  single  plant,  and  that  when  present  the 
number  varies  from  5  to  1.  The  size  also  is  variable,  while  the  tendency  toward  com- 
plete reduction  is  not  characteristic  of  plants  of  any  particular  geographic  area,  and  can 
not  be  correlated  with  other  characters.  Most  of  these  facts  are  perhaps  sufficiently 
well  brought  out  in  table  25,  which,  however,  lists  only  a  portion  of  the  collections  exam- 
ined. The  others  all  point  in  the  same  direction.  The  lack  of  concomitance  between 
width  of  leaf  and  the  presence  or  absence  of  scales  is  incompletely  shown  by  figure  32. 
Further  evidence  is  furnished  by  plants  from  Fresno  County,  Cahfornia,  (Kearney  21, 
US),  which  although  having  comparatively  narrow  leaves,  as  in  the  type  of  covillei,  have 
no  perianth  in  the  pistillate  flowers.  This  collection  carries  genuine  phyllostegia  into 
middle  California,  while  only  covillei  is  accredited  to  this  State  in  the  North  American 
Flora,  a  peculiarity  in  distribution  to  be  taken  into  account  by  those  who  would  retain 
the  latter  in  specific  rank. 

The  conclusion,  therefore,  is  that  Atriplex  phyllostegia  is  in  a  fluctuating  condition  as 
far  as  the  perianth  of  the  pistillate  flowers  is  concerned.  This  structure  is  to  be  looked 
upon  merely  as  a  vestige,  sometimes  consisting  of  several  much  reduced  sepals,  but 


A.    CORDULATA. 


269 


varying  to  a  single  minute  scale  and  entirely  disappearing  in  many  cases.  It  possesses 
no  value  in  classification  and  its  presence  or  absence  can  not  be  used  as  a  taxonomic  crite- 
rion. Finally,  many  other  features  of  this  remarkable  plant  are  also  variable,  giving  to  the 
species  a  degree  of  plasticity  which  enables  it  readily  to  adapt  itself  to  varying  ecologic 
conditions.  Some  of  these  additional  variations  were  responsible  for  A.  draconis  Jones, 
a  proposed  species  reduced  to  A.  phyllostegia  on  evidence  supplied  by  the  type  specimens, 
which  were  generously  made  available  by  Professor  Jones.  (See  further  under  minor 
variation  2  of  the  above  Hst.) 

Table  25. — Variation  in  pistillate  flowers  of  Atriplex  phyllostegia. 


Collection. 

Herbarium. 

Perianth. 

Quinn  River  crossing,  northern  Nevada.  Griffiths  and  Morris  108 

402572  US 
402569  US 
359070  US 
Gr 
419436  US 

Jones 

505740  US 

185923  UC 

US 

Jones 

48313  US 

Gr.  US 

939200  US 

468781  US 

278942  US 

410815  US 

None. 
None. 
None. 
None. 

4  scales. 
None. 

3  scales. 

5  scales. 

2  scales. 
Varies.  0  to  2.» 

3  scales. 
Minute  scales. 

3  withscales,  1  with  no  scales. 

3  scales 

2  flowers  with  scales,  2  without. 

None.' 

Eagle  Valley   western  Nevada   Baker  1251                                             .    ■  ■ 

Ash  Meadows  Ranch,  southwestern  Nevada.  Coville  and  Funston  370.. . 
Amargosa  Desert,  southwestern  Nevada,  April  26,  1907.  Jones 

Mojave  Desert   Calif    July  4    1882   Pringle 

Rabbit  Springs   Mojave  Desert   Calif    Parish  1346 

Near  Tulare  Lake   Calif    Palmer  2707                               

'  Watson  included  two  collections  under  his  986,  either  of  which  may  be  taken  as  the  type.  Both  are  from  western 
Nevada  and  no  perianth  has  been  found  in  either  of  them. 

>  Type  of  A.  draconis  Jones,  minor  variation  2. 

•Ten  flowers  were  examined  of  this  collection;  two  of  these  were  devoid  of  perianth,  each  of  the  others  had  1  or  2 
small  scales. 

•  Type  of  Endolepis  covillei  Standley,  minor  variation  3. 

«  The  result  of  10  examinations. 

ECOLOGY  AND  USES. 

Atriplex  phyllostegia  may  occur  in  clan-hke  groups  in  strongly  saline  soil,  where  it  is 
associated  with  Sarcobatus,  Chrysothamnus  nauseosus  consimilis,  and  Distichlis,  or  it  may 
form  families  of  some  size  in  depressions  in  fallow  fields  and  alkaline  plains,  especially 
where  Distichlis  has  been  plowed  or  otherwise  disturbed.  It  is  an  indicator  of  strong 
alkali,  to  an  amount  of  3  to  4  per  cent  in  the  first  foot,  where  the  roots  occur.  The  plants 
bloom  for  an  unusually  long  period,  namely,  April  to  September,  apparently  in  conse- 
quence of  the  relatively  constant  water-content. 

This  species  is  doubtless  grazed,  but  it  is  too  inconsiderable  to  be  important. 

12.  ATRIPLEX  CORDULATA  Jepson,  Pittonia  2 : 304,  1892.  Plate  43.  Heartscale. 
Erect  rigid  annual  herb  or  spreading  as  the  result  of  grazing,  1  to  5  dm.  high,  either  sim- 
ple or  branched  throughout;  branches  heavy,  rigid,  not  angled,  furfuraceous,  glabrate  in 
age,  the  bark  then  stramineous  and  exfoliating;  leaves  alternate  except  the  lower,  closely 
sessile,  ovate,  all  cordate  at  base  except  the  lowest  which  are  merely  rounded  to  a  slightly 
narrowed  base,  acute  at  apex,  0.5  to  1.5  cm.  long,  0.3  to  1  cm.  wide,  entire,  rather  thick, 
heavily  coated  with  a  furfuraceous  tomentum  which  is  only  tardily  deciduous,  the  veins 
then  conspicuous;  flowers  monoecious,  in  dense  glomerules  in  the  axils  of  all  but  the  few 
lowermost  leaves,  the  staminate  confined  to  the  upper  axils  but  not  forming  naked  spikes; 
perianth  4-cleft  or  5-cleft  in  the  staminate  flowers,  wanting  in  the  pistillate ;  fruiting  bracts 
sessile  or  subsessile,  lightly  compressed,  united  to  about  the  middle,  typically  ovate  from 
a  broad  base,  often  slightly  rounded  to  a  very  short  stalk,  usually  broadest  below  but 


270 


GENUS   ATRIPLEX. 


sometimes  at  the  middle  or  even  slightly  above  (and  then  approaching  flabelliform)  by 
an  exceptional  development  of  the  free  margins,  4  to  5  mm.  long,  4  to  5  mm.  broad,  the 
green  foliaceous  margins  irregular  and  acutely  dentate,  the  faces  smooth  (except  for  a 
dense  scurf)  or  with  only  a  few  short  protuberances;  seed  1.5  to  1.8  mm.  long,  deep  red- 
dish-brown, nearly  black,  shining;  radicle  superior. 


© 


Lvs.  cordate  Lvs.  rounded  at 

at  base ;  bracts       base ;  bracts 
*-5mm.long  2.5-J.5mm. 

long 


Fm.  33. — Phylogenetic  chart  of  the  Alriplex  pusiUa  group. 

Confined  to  California;  Sacramento  and  San  Joaquin  Valleys;  most  common  in  the 
latter.  Type  locality,  near  Little  Oak  (just  southeast  of  Vacaville),  Solano  County,  Cal- 
ifornia. Collections:  North  of  Norman,  Glenn  County,  scarce.  Hall  11007  (UC);  type 
collection,  August  16,  1892,  Jepson  (Herb.  Jepson,  NY,  US);  near  Stockton,  July 
17,  1896,  Jepson  (Herb.  Jepson);  near  Volta,  Merced  County,  September  21,  1918, 
Severin  (UC,  strict,  mostly  simple-stemmed);  same  locality,  July  20,  1920,  Hall  11017 
(UC,  both  simple-stemmed  and  widely  branched  plants);  16  km.  south  of  Merced, 
October  25,  1919,  Hall  (UC);  near  Chowchilla,  Madera  County,  Hall  11787,  11790 
(UC);  Earlimart,  Tulare  County,  Hall  11786  (UC);  between  Tulare  and  Tulare  Lake, 
Palmer  2727  (NY,  immature). 

RELATIONSHIPS. 

This  species  stands  between  A.  argentea  and  the  group  of  small-fruited  species  assem- 
bled by  Standley  under  the  sectional  name  Pusillae.  In  general  appearance,  especially 
the  robust  habit,  it  is  more  like  the  former.  The  bracts,  however,  are  more  like  those  of 
the  latter,  since  they  are  for  the  most  part  widest  below  the  middle.  They  are  larger 
than  any  in  the  other  species  of  the  Pusillae  and  when  the  free  margins  are  exceptionally 


A.    TULARENSIS  271 

well  developed  the  outline  sometimes  approaches  obovate,  the  bracts  then  simulating 
those  of  the  argentea  group,  even  though  the  body  itself  is  broadest  at  or  below  the  mid- 
dle. The  bracts  most  closely  resemble  those  of  A.  coronata,  under  which  species  the 
differentiating  characters  will  be  discussed. 

The  phylogenetic  position  of  cordulata  at  the  beginning  of  the  Pusillae  seems  to  be  well 
established.  It  is  less  highly  specialized  than  any  of  the  others,  each  of  which  has  under- 
gone considerable  reduction  in  the  size  of  the  foliage,  flowers,  fruiting  bracts,  and  seeds. 
The  development  of  certain  other  features  will  be  pointed  out  later. 

There  has  been  no  notable  development  of  important  variations  within  A.  cordulata. 
This  condition  is  associated  with  its  restricted  distribution.  Two  habit  forms  may  be 
recognized,  however.  These  are  very  unlike  in  their  extreme  development,  yet  all  inter- 
vening stages  are  known  and  sometimes  both  are  found  at  the  same  locality.  They  are 
illustrated  even  in  the  type  material,  which  consists  of  three  sheets  with  identical  labels, 
except  that  one  sheet  is  noted  as  the  "small,  strict  form."  This  holds  2  plants,  only  1.5 
and  2  dm.  high,  respectively.  One  is  simple-stemmed,  the  other  has  one  very  short 
branch.  The  other  sheets  have  much  taller  and  stouter  plants,  one  with  5  branches  from 
the  base,  each  again  forked,  another  with  trunk-like  leader  and  several  strong  lateral 
branches.  Robust  and  much-branched  bushy  plants  might  easily  be  taken  for  a  distinct 
species  were  it  not  for  the  close  similarity  to  the  simple-stemmed  dwarfs  in  all  essential 
characters  and  the  presence  of  intermediate  forms.  Branching  from  the  base  is  undoubt- 
edly due  to  injury  to  the  main  shoot,  most  commonly  as  the  result  of  grazing.  The 
remarkably  strict  habit  has  been  noted  by  Jepson  (1.  c),  who  writes: 

"The  leaves  on  the  virgate  branches  are  much  alike  in  size  and  form;  they  are  triple-nerved  and  almost  as 
broad  as  long;  the  lowest  are  rarely  five  lines  long.  The  stem  is  sometimes  absolutely  strict,  but  usually  the 
species  is  distinguished  by  its  virgate  branches.  Sometimes  the  stems  bear  numerous  very  short  branches 
which,  however,  rob  the  plant  of  nothing  of  its  virgate  aspect." 

ECOLOGY  AND  USES. 

Atriplex  cordulata  grows  in  hard,  trampled  soil  that  is  only  moderately  alkaline.  It 
may  form  pure  stands  in  open  spots  in  Salicornia,  Frankenia,  etc.,  or  occur  scattered  in 
Distichlis  turf  with  Heliotropium  curassavicum,  Hemizonia  pungens,  or  Helianthus  annuus. 
The  flowers  open  from  April  to  September. 

This  is  a  host-plant  of  Eulettix,  the  relations  of  which  are  described  under  A.  bracteosa. 

13.  ATRIPLEX  TULARENSIS  Coville,  Contr.  U.  S.  Nat.  Herb.  4:182,  plate  19, 1893. 
Plate  41. 

Erect  rigid  but  slender  annual  herb,  2  to  10  dm.  high,  either  simple  or  with  strict  ascend- 
ing or  erect  stems,  these  sometimes  from  the  base;  branches  rigid,  brittle,  terete  or  very 
obscurely  angled,  coarsely  white-scurfy,  early  turning  red,  glabrate  only  near  the  root, 
many  lateral  branches  of  the  upper  parts  arrested  in  their  growth  and  forming  very  short 
imbricate-leaf y  shoots  in  the  leaf-axils ;  leaves  alternate  except  2  or  3  lower  pairs,  sessile 
or  subsessile,  ovate  to  lanceolate,  rounded  to  the  base,  acute  or  acuminate  at  apex,  1  to  2 
cm.  long,  0.4  to  0.8  cm.  wide,  entire,  thin  but  firm,  gray  with  a  dense  scurf,  l-nerved, 
sometimes  with  2  additional  faint  nerves  from  the  base;  flowers  monoecious,  in  small 
dense  axillary  glomerules,  the  lower  of  which  are  purely  pistillate,  the  upper  purely  stam- 
inate,  the  sexes  mixing  in  some  of  the  intermediate  axils;  perianth  4-cleft  in  the  staminate 
flowers,  wanting  in  the  pistillate,  fruiting  bracts  sessile,  lightly  compressed,  united  nearly 
to  summit,  ovate  in  outline  or  some  with  narrowed  base  and  then  rhomboid  and  broadest 
at  about  the  middle,  2.5  to  3.5  mm.  long,  2.2  to  3  mm.  broad,  the  thin  margins  few-  to 
many-toothed,  or  only  erose,  the  apex  usually  ending  in  a  prominent  ovate  acute  tooth, 
the  faces  neither  tubercled  nor  appendaged  but  covered  with  a  dense  gray  scurf;  seed  1 
to  1.2  mm.  long,  dark  brown,  shining;  radicle  superior. 


272  GENUS   ATRIPLEX. 

Known  only  from  alkaline  plains  of  the  southern  part  of  the  San  Joaquin  Valley,  Cali- 
fornia. Type  locality,  about  25  km.  south  of  Bakersfield,  Kern  County,  California. 
Collections,  all  in  California:  type  collection,  July  13,  1891,  Coville  1235  (UC,  US);  same 
locality,  Severin  and  Hall  11782  (UC);  plains  13  km.  south  of  Bakersfield,  Severin  and 
Hall  1178S  (UC);  plains  south  of  Bakersfield,  Davy  2897  (UC). 

SYNONYM. 

1.  Atriplex  cordulata  var.  tclarensis  Jepson,  Fl.  Calif.  436, 1914. — A.  tularemis. 
RELATIONSHIPS. 

This  species  is  closely  related  to  A.  cordulata,  as  was  expressed  by  Jepson  in  the  above- 
quoted  combination.  Recent  and  detailed  field  studies  of  both  species  indicate,  how- 
ever, that  they  are  not  connected  by  intermediate  forms.  In  judging  from  comparisons 
between  the  two  as  they  grow  under  natural  conditions,  one  would  scarcely  suspect 
them  of  being  related.  Also  in  detail  there  is  sufficient  difference  for  specific  recognition. 
A.  tularensis  is  a  much  more  slender  plant,  the  leaves  are  narrower  in  proportion  to  their 
length  and  never  at  all  cordate  at  the  base  as  in  cordulata,  but  narrowed  below.  The 
shape  of  leaf  is  remarkably  constant  in  both  species.  The  fruiting  bracts  are  sometimes 
very  similar  in  shape,  but  those  of  tularensis  typically  end  in  an  abrupt  acute  tooth  not 
present  in  cordulata  and  both  bract  and  seed  are  always  smaller. 

The  small  size  of  the  bracts  and  their  shape  in  some  cases  are  very  suggestive  of  a 
connection  with  A.  pusilla  and  its  allies.  For  these  reasons  A.  tularensis  was  placed  in 
the  section  Pusillae  by  Standley  (N.  Am.  Fl.  21 :50,  1916).  It  seems  impossible  to  deter- 
mine at  the  present  time  whether  the  direction  of  evolution  was  from  cordulata  through 
tularensis  and  then  on  to  the  true  Pussillae  by  reduction  in  essentially  all  characters,  or 
whether  these  last  have  developed  from  some  entirely  different  source,  such  as  A.  wolfi. 
ECOLOGY  AND  USES. 

Atriplex  tularensis  grows  typically  in  grassy  alkaline  flats  in  the  southern  portion  of  the 
San  Joaquin  Valley,  where  it  is  associated  with  Distichlis,  Elymus  condensatus,  and  Sporo- 
holus  asperifolius.  It  extends  to  the  edge  of  the  Salicornia  belt,  but  is  absent  wherever 
Salicornia  or  Spirostachys  occurs.  It  does  not  form  distinct  communities,  but  grows 
scattered  among  the  grasses,  apparently  holding  its  own  in  the  competition.  The  flowers 
occur  from  July  to  October. 

The  plants  are  grazed  along  with  the  grasses,  repeated  cropping  giving  them  the 
branched  form  typical  of  pastures.  They  are  also  hosts  of  the  beet  leaf-hopper,  but  of 
restricted  importance  because  of  the  limited  range  of  the  species. 

14.  ATRIPLEX  PUSILLA  (Torrey)  Watson.  Proc.  Am.  Acad.  9: 110,  1874.    Plate  41. 
Smallscale. 

Erect  annual  herb,  0.5  to  2  dm.  high,  freely  branched  throughout  but  especially  at  the 
base;  branches  slender,  not  angled,  sparsely  furfuraceous,  glabrate  below,  early  becoming 
reddish;  leaves  all  alternate,  except  1  or  2  lower  pairs,  crowded  and  imbricate  above, 
sessile,  ovate  or  elliptic,  narrowed  or  rounded  to  the  base,  acute  at  apex,  0.5  to  1.5  cm. 
long,  0.3  to  0.6  cm.  wide,  entire,  thickish,  somewhat  fleshy,  gray  with  a  dense  scurf  or 
this  sparse  and  the  foliage  then  greenish,  1-nerved;  flowers  monoecious,  usually  1  in  each 
leaf-axil,  sometimes  2,  the  staminate  near  the  ends  of  the  branchlets  but  never  in  naked 
terminal  spikes;  perianth  either  4-  or  5-cleft  in  the  staminate  flowers,  wanting  in  the  pis- 
tillate; fruiting  bracts  sessile,  not  compressed,  united  to  the  apex  (united  half  their  length, 
according  to  Torrey,  but  this  apparently  an  error),  ovate,  abruptly  acute,  1  to  1.5  mm. 
long,  about  1  mm.  broad,  not  margined,  entire,  the  faces  smooth;  seed  0.8  mm.  long,  yel- 
lowish-brown (perhaps  darker  when  mature) ;  radicle  superior.  {Obione  pusilla  Torrey, 
in  Watson,  Bot.  King's  Expl.  291,  1871.) 


A.    PUSILLA — A.    TENUISSIMA.  273 

Northern  Nevada,  southeastern  Oregon,  and  northeastern  Cahfornia;  range  doubtless 
more  extensive,  but  the  plants  easily  overlooked.  Type  locality,  near  Carson  City  and 
on  the  edge  of  a  dry  alkali  flat  near  the  head  of  Humboldt  Valley,  Nevada.  Collections: 
Nevada:  Humboldt  Valley,  1,220  m.  altitude,  Watson  988  (Gr,  NY,  one  of  the  type 
collections);  Camp  Halleck,  Humboldt  River  Valley,  Palmer  ^54  (Gr);  4  km.  west  of 
Wells,  Humboldt  River  Valley,  Hall  11033  (UC);  2  km.  northeast  of  Wells,  Hall  IIOS4 
(UC) ;  near  Carson  City,  Anderson  65  (Gr,  NY,  one  of  the  tjrpe  collections) ;  same  locality, 
June  4,  1897,  Jones  (Herb.  Jones);  Harney  Valley,  Oregon,  Howell  537  (Gr);  same  local- 
ity, Cusick  1663  (DS,  Gr,  UC);  Chat,  eastern  Lassen  County,  California,  June  19,  1897, 
Jones  (Herb.  Jones);  "California,"  August  and  September,  1872,  Torrey  (US). 

SYNONYM. 
1.  Obione  PUSILLA  Torrey,  in  Watson,  Bet.  King's  Expl.  291,  1871. — Alriplex  pusilla. 

RELATIONSHIPS. 

This  was  the  first  described  species  of  a  small  group  of  Atriplexes  characterized  by  the 
small  size,  slender  branching  habit,  and  minute  ovate  fruiting  bracts  borne  singly  or  at 
least  sparsely  in  the  leaf -axils.  It  differs  from  the  others,  that  is,  from  A .  lenuissima  and 
A .  parishi,  in  the  even  smaller  and  uniformly  smooth  bracts,  as  well  as  in  details  of  habit 
and  leaf.  These  bracts  are  remarkably  constant  in  their  shape,  which  is  ovate  with 
abruptly  narrowed  tips,  and  in  the  total  absence  of  teeth  and  appendages.  These  char- 
acters hold  for  all  herbarium  specimens  examined  and  for  several  hundred  plants  studied 
in  the  field,  mostly  in  the  vicinity  of  Wells,  Nevada. 

The  origin  of  A.  pusilla  is  not  known.  In  habit  it  is  most  like  A.  wolfi,  a  more  easterly 
species,  but  the  fruiting  bracts  of  that  are  so  highly  specialized  in  shape  that  their  modi- 
fication into  the  more  primitive  ovate  type  seems  scarcely  probable.  As  far  as  the  bracts 
are  concerned,  it  might  be  looked  upon  as  a  derivative  of  the  Calif ornian  A.  tularensis, 
in  which  the  bracts  have  lost  their  dentations  and  been  much  reduced  in  size.  But  in 
other  features  these  two  are  very  unlike.  When  compared  with  the  other  species  {lenuis- 
sima and  parishi)  of  its  own  small  group,  it  is  seen  that  pusilla  can  not  be  taken  as  the 
beginning  of  this  branch,  because  of  its  greatly  reduced  and  otherwise  modified  bracts  and 
seeds.  Neither  can  it  be  considered  as  a  derivative  of  either  of  the  other  members,  since 
each  of  these  exhibits  strongly  specialized  features.  Thus,  it  becomes  necessary  to  con- 
sider each  of  the  three  species  as  an  isolated  phylogenetic  unit.  Taken  together  they 
form  a  natural  group  which  probably  originated  through  a  divergence  from  the  main  line 
somewhere  near  A.  cordulata  and  A.  tularensis  and  before  either  leaves  or  bracts  had 
assumed  the  oblanceolate,  obovate,  or  cuneate  shape. 

ECOLOGY  AND  USES. 

Atriplex  pusilla  is  a  delicate  annual  that  forms  pure  socies  on  alkaline  flats  between 
bushes  of  Sarcobatus,  or  grows  in  disturbed  spots  in  communities  of  Sarcobatus,  Distichlis, 
and  A.  rosea.     The  plants  bloom  from  June  through  August. 

This  species  is  too  delicate  and  too  rare  to  be  of  economic  importance. 

15.  ATRIPLEX  TENUISSIMA  Nelson,  Bot.  Gaz.  34:359,  1902.     Plate  41. 

Erect  annual  herb  1.5  to  3  dm.  high,  intricately  branched  throughout;  branches  slender, 
elongated,  ascending,  sometimes  zigzag,  not  angled,  moderately  white-scurfy  to  the  base, 
reddish  except  near  the  ends;  leaves  alternate  except  perhaps  the  lower,  numerous, 
sessile,  lance-ovate  to  linear  (especially  in  minor  variation  1,  .4.  greenei  Nelson),  rounded 
to  the  base,  acute  at  apex,  1  to  2  cm.  long,  0.2  to  0.3  cm.  wide,  thickish,  densely  gray- 
scurfy,  1-nerved;  flowers  monoecious,  several  in  each  of  the  leaf -axils  except  near  the  base 


274  GENUS   ATRIPLEX. 

of  the  plant,  the  staminate  confined  to  a  few  of  the  upper  axils;  perianth  5-cleft  in  the 
staminate  flowers,  wanting  in  the  pistillate;  fruiting  bracts  sessile,  thick,  united  nearly 
to  apex,  ovate,  acute,  2  to  3  mm.  long,  1.5  to  2.2  mm.  broad,  not  margined,  sparsely  and 
minutely  toothed  along  the  edges,  the  faces  bearing  a  few  short  acute  tubercles,  especially 
across  the  middle;  seed,  1  to  1.2  mm.  long,  yellowish-brown;  radicle  superior. 

Known  only  from  southwestern  Wyoming  and  eastern  Utah.  Type  locality,  Gunnison, 
Utah,  altitude  about  1,600  m.  Collections:  Type  collection,  September  15, 1900,  Jones 
6525  (Herb.  Jones,  NY,  St.  Louis,  UC) ;  Rock  Springs,  Wyoming,  August  9,  1896,  Greene 
(R,  NY,  UC,  type  collection  of  A.  greenei  Nelson,  minor  variation  1). 

MINOR  VARIATION. 

1.  Atriplex  greenei  Nelson,  Bot.  Gaz.  56: 65,  1913. — Differs  in  having  narrowly  linear  leaves,  the  larger  of 
which  are  1  to  1.5  cm.  long  by  only  1.5  mm.  wide,  and  in  the  bracts,  which  are  described  as  appendaged  at  the 
middle  or  above.  The  leaves  in  the  type  of  tenuissima  are  described  as  oblong  to  lance-ovate  or  broader,  1  to  7 
mm.  long;  in  the  only  material  now  at  hand  (duplicates  of  the  type)  they  are  mostly  ovate  to  linear-oblong,  the 
widest  5  mm.  long  by  2.5  mm.  wide.  But  proceeding  down  the  stem,  the  leaves  progressively  approach  the 
linear  shape  of  greenei,  one  measuring  6.6  mm.  long  by  2  mm.  wide.  The  bract  differences  are  as  described  as 
far  as  the  general  tendency  is  concerned.  That  the  difference  in  the  distribution  of  the  appendages  is  not  so 
sharp  as  supposed  is  indicated  by  the  accompanying  text-figures.  The  single  collection  thus  far  made  of  each 
of  these  forms  does  not  furnish  sufficient  evidence  for  the  final  disposal  of  A.  greenei,  either  as  a  distinct  species 
or  as  a  minor  variation  of  A.  tenuissima,  but  from  the  nature  of  the  differentiating  characters  it  is  predicted 
that  intermediate  forms  will  be  found,  in  which  case  the  latter  will  be  the  preferred  course. 


Fio.  34. — Fruiting  bracts  of  Atriplex  tenuissima  to  illustrate  the  distribution  of  appendages  in  the  type  and  in  a  minor  varia- 
tion: a,  b,  c,  d,  bracts  from  the  type  specimen  (Missouri  Botanical  Garden  Herbarium);  e,  /,  g,  bracts  from  the 
type  specimen  of  minor  variation  1,  A.  greenei  Nelson  (Rocky  Mountain  Herbarium);  h,  bract  from  a  duplicate 
of  A.  greenei  (New  York  Botanical  Garden  Herbarium).     All  X  6. 

RELATIONSHIPS. 

Atriplex  tenuissima  is  most  closely  related  to  A.  pusilla,  but  is  sharply  set  off  by  its 
more  numerous  flowers  in  each  of  the  glomerules  and  especially  by  its  larger  and  con- 
stantly tuberculate  fruiting  bracts  and  larger  seeds.  The  relationship  to  this  species  and 
the  probable  origin  of  the  group  are  discussed  under  A.  pusilla.  In  describing  the  type, 
which  is  at  the  herbarium  of  the  Missouri  Botanical  Gardens,  Nelson  says  that  only  the 
pistillate  plant  was  seen.  However,  the  species  is  not  dioecious,  for  duplicates  of  the 
type  collection  bear  both  kinds  of  flowers.  It  is  probable  that  the  staminate  flowers 
had  all  matured  and  dropped  from  the  plant  examined  by  Nelson.  In  the  only  other  col- 
lection (Rock  Springs,  Wyoming,  Greene)  the  plants  are  also  monoecious. 

ECOLOGY  AND  USES. 

Nothing  is  known  concerning  the  ecologic  relations  of  this  species,  but  probably  they 
are  similar  to  those  of  A.  pusilla.     It  has  no  uses. 

16.  ATRIPLEX  PARISH]  Watson,  Proc.  Am.  Acad.  17:377,  1882.  Plate  41.  Brittlescale. 
Erect  but  often  seemingly  prostrate  rigid  annual  herb,  0.5  to  2  dm.  high,  widely 
branched  throughout;  branches  numerous,  rather  stout,  brittle,  often  horizontally  spread- 
ing, coarsely  white-scurfy,  the  scurf  sometimes  so  long  as  to  simulate  a  true  pubescence, 
tardily  glabrate,  faintly  tinged  with  red;  leaves  varying  from  all  opposite  to  mainly  alter- 
nate, numerous,  the  upper  ones  imbricate,  closely  sessile,  ovate,  the  lower  lanceolate, 


A.    PARISHI. 


275 


broadly  rounded  to  the  base,  acute  at  apex,  0.4  to  1  cm.  long,  0.3  to  0.5  cm.  wide,  entire, 
rigid,  gray  or  nearly  white  with  a  dense  scurf,  1-nerved;  flowers  monoecious,  several  in 
each  of  the  leaf-axils,  the  staminate  in  the  middle  and  upper  axils,  the  pistillate  in  the 
middle  and  lower  axils;  perianth  of  staminate  flowers  4-  or  5-cleft,  wanting  in  the  pistil- 
late; fruiting  bracts  sessile,  slightly  compressed,  united  to  a  little  above  the  middle,  ovate 
or  rhomboidal,  often  subhastately  lobed,  acute,  2.5  to  3.5  mm.  long,  2.5  to  3  mm.  broad, 
narrowly  margined,  entire  or  with  a  prominent  tooth  on  each  side,  the  faces  smooth  to 
muricate;  seed  about  1.2  mm.  long,  dark  brown  or  nearly  black  when  fully  mature; 
radicle  superior. 

California,  from  the  upper  Sacramento  Valley  nearly  to  the  southern  border,  east  to  the 
edges  of  the  Mojave  and  Colorado  Deserts.  Type  locality,  Costa  Station,  Los  Angeles 
County  (now  Almond,  Orange  County),  California.  Collections,  all  from  California  (all 
but  the  last  7  referable  to  minor  variation  1,  A.  depressa  Jepson,  and  some  also  to  minor 
variation  2,  A.  minuscula  Standley):  Willows,  Glenn  County,  Hall  11005  (UC);  near 
Norman,  Glenn  County,  Hall  11006,  11013  (UC);  west  of  Vanden,  Solano  County,  Sep- 
tember 22,  1891,  Jepson  (Herb.  Jepson,  type  of  A.  depressa  Jepson,  minor  variation  1, 
also  US);  Altamont  Pass,  Hall  10975  (CI);  2  km.  north  of  Volta,  Merced  County,  July 
20,  1920,  Hall  (CI);  Laton,  Fresno  County,  Kearney  33  (US,  lower  leaves  opposite,  the 
upper  all  alternate) ;  same  locality,  Kearney  34  (US,  all  leaves  opposite) ;  20  km.  east  of 
Dos  Palos,  Fresno  County,  Hall  11756  (UC);  near  Chowchilla,  Madera  County,  Hall 
11759,  11789  (UC);  Goshen,  Tulare  County,  about  the  station,  September  1,  1905, 
Brandegee  (UC);  Visalia,  Tulare  County,  October,  1881,  Congdon  (UC);  between  Tulare 
and  Tulare  Lake,  Palmer  2728  (US,  type  of  A.  minuscula  Standley,  minor  variation  2); 
Cushenberry  Spring,  south  edge  of  Mojave  Desert,  Parish  (US);  Bixby,  Los  Angeles 
County,  Brandegee  (UC);  type  collection,  October,  1881,  Parish  1119  (DS,  Gr,  US); 
Santa  Monica,  Davidson  2936  (US) ;  brackish  flats  near  Cahuenga,  Los  Angeles  County, 
Hasse  5670  (NY);  alkali  flats,  Laguna,  Orange  County,  May,  1907,  Minthorn  (UC); 
southeastern  base  of  San  Jacinto  Mountain,  at  Vandeventer  Flat,  Hall  2146  (DS,  NY, 
UC,  US);  Coahuila  Hot  Springs,  San  Diego  County,  Parish  1119a  (Gr). 

MINOR  VARIATIONS. 

1.  Atriplex  depressa  Jepson,  Pittonia  2:304,  1892.— This  has  been  reduced  to  A.  parishi  by  Jepson  (Fl. 
Calif.  436, 1914),  a  disposal  with  which  the  present  authors  agree.  It  was  retained  by  Standley  (N.  Am.  Fl.  21 : 
50,  1916)  principally  on  three  characters,  namely,  the  branches  not  "copiously  villous,"  the  alternate  leaves,  and 
the  slightly  smaller  fruiting  bracts.  A  re-examination  of  the  types  and  of  extensive  collections  now  at  hand 
proves  only  the  first  of  these  to  be  of  value  and  even  this  is  of  but  minor  importance.  In  the  type  of  parishi  and 
in  three  other  collections  from  southern  California  the  branches,  especially  near  the  ends,  are  apparently  villous, 
while  in  all  material  from  farther  north,  that  is,  from  the  area  of  depressa,  the  branches  are  merely  scurfy. 
But  this  difference  is  one  of  degree  only,  for  the  "villosity"  of  the  southern  plants  is  due  to  the  same  trans- 
parent scurf  as  found  in  northern  plants,  except  that  the  individual  scales  are  more  elongated  and  therefore 
hair-like.  Since  this  elongation  of  the  scurf  is  a  constant  feature  of  all  of  the  southern  plants,  of  which,  how- 
ever, there  are  only  four  collections,  it  may  suffice  for  those  who  draw  exceedingly  fine  lines  between  species. 
As  to  the  opposite  arrangement  of  the  leaves,  this  can  be  associated  neither  with  the  character  just  mentioned 
nor  with  geographic  distribution.  For  example,  in  Madera  County,  California,  opposite-leaved  and  alternate- 
leaved  plants  grow  side  by  side,  and  plants  with  leaves  partly  opposite  and  partly  alternate  are  not  uncommon 
in  the  San  Joaquin  Valley  (e.  g..  Hall  11756,  UC,  and  cf.  plate  41,  fig.  16).  The  type  of  A.  parishi  at  the  Gray 
Herbarium  has  mostly  alternate  leaves.  A  duplicate  of  the  same  collection  at  the  United  States  National 
Herbarium  has  only  opposite  leaves,  or  an  occasional  leaf  slightly  displaced  from  its  opposite  position. 
Finally,  as  to  size  of  bract,  an  examination  of  the  type  of  depressa  discloses  the  fact  that  mature  bracts  are  3 
mm.  long,  exactly  the  size  given  for  parishi  (see  plate  41,  fig.  22).  The  average  size  of  the  bracts  of  northern 
plants  is  about  the  same  as  that  of  bracts  from  southern  specimens.  Thus  depressa,  if  retained  as  a  taxonomic 
unit,  must  be  based  solely  upon  the  shorter  scurf  of  the  branches,  a  character  which  doubtless  will  be  found 
to  be  variable  as  further  collections  become  available  for  study.  The  type  locality  is  "low  saline  spots,  near 
the  alkaline  springs,  point  of  the  Pelevo  Hills,  west  of  Vanden,"  Solano  County,  California. 


276  GENUS   ATRIPLEX. 

2.  A.  MiNCSctJLA  Standley,  N.  Am.  Fl.  21 :51,  1916. — No  characters  can  be  found  upon  which  to  retain  this 
proposal  as  distinct  from  parishi.  The  scurf  of  the  branches  consists  merely  of  short  scales,  as  in  the  preceding 
variation,  under  which  the  value  of  this  feature  is  discussed.  The  leaves  are  mostly  alternate,  as  in  typical  par- 
ishi, but  leaf-scars  and  branches  on  the  type  indicate  opposite  leaves  for  about  one-fourth  the  way  up.  The 
fruiting  bracts  are  2  to  3  mm.  long  and  smooth  on  the  sides,  although  the  margins  are  dentate  or  crenulate.  The 
presence  or  absence  of  appendages  is  much  too  variable  a  character  to  be  used  here.  Both  kinds  of  bracts  are 
often  found  on  the  same  plant  and  in  .some  cases  even  in  the  same  pair  (see  for  example,  plate  41,  fig.  22). 
It  has  been  noticed  that  on  some  plants  one  bract  of  each  pair,  namely,  the  one  facing  the  adjacent  leaf,  is 
smooth,  whereas  the  one  on  the  stem  side  is  muricate;  thus,  since  the  fruits  are  horizontal  all  of  them  appear  to 
be  muricate  as  one  looks  from  above  upon  the  living  plant  {Hall  11005).  Type  locality,  between  Tulare  and 
Tulare  Lake,  California. 

RELATIONSHIPS. 

This  species  belongs  to  a  group  of  three,  the  origin  and  relationships  of  which  are  but 
little  known.  The  probable  connections  have  been  indicated  under  A.  pusilla.  In 
connection  with  the  original  description,  Watson  stated  that  A.  parishi  belonged  to  the 
paiula  group,  but  the  superior  radicle,  as  well  as  an  absence  of  similarity  in  nearly  all 
other  features,  indicates  that  this  was  an  erroneous  assignment.  The  short,  stiff,  scale- 
like leaves  and  the  very  rigid  stems,  which  become  brittle  and  break  into  short  joints  at 
maturity,  are  unhke  those  of  any  other  Atriplex.  The  plants  have  been  described  as 
prostrate,  but  they  are  perhaps  never  truly  so,  except  by  injury  to  the  main  axis  or 
through  trampling.  However,  the  lateral  branches  commonly  spread  horizontally, 
so  that  the  lower  ones  recline  on  the  ground  and  in  some  herbarium  specimens  all  are 
flattened  out  and  apparently  prostrate.  The  outline  of  the  whole  plant  when  permitted 
to  develop  normally  is  approximately  hemispheric,  as  shown  in  the  thumb  sketch  (plate 
41). 

ECOLOGY  AND  USES. 

Atriplex  parishi  forms  families  in  areas  of  white  alkali,  often  surrounded  by  Distichlis, 
or  mixes  with  A.  fruticulosa  and  Distichlis  in  similar  areas.  It  also  occurs  on  disturbed 
'saline  soil  with  Frankenia.  It  is  evidently  more  resistant  to  alkali  than  is  Hemizonia 
pungens,  as  it  grows  vigorously  where  the  latter  is  small  and  sparse.  The  plants  bloom 
from  May  to  September. 

This  is  an  important  host-plant  of  Eutettix  in  the  San  Joaquin  Valley. 

17.  ATRIPLEX  TRUNCATA  (Torrey)  Gray,  Proc.  Am.  Acad.  8:398,  1872.    Plate  42. 
Wedgescale. 

Erect  annual  herb  (somewhat  decumbent  in  minor  variation  2,  A.  subdecumbens  Jones), 
2  to  10  dm.  high,  with  ascending  branches  throughout  or  unbranched  (minor  variation  1, 
variety  stricta  Gray) ;  branches  slender,  angled,  lightly  furfuraceous,  early  glabrate,  the 
bark  then  dull-white  or  reddish;  leaves  alternate  or  the  lower  ones  perhaps  opposite, 
mostly  sessile,  deltoid  or  triangular-ovate  or  rounded-ovate,  rarely  approaching  oval, 
broad  and  truncate  or  subhastate  or  rarely  rounded  at  base,  acute  or  obtuse  at  apex,  1 
to  3  or  4  cm.  long,  0.8  to  2  cm.  wide,  entire  or  only  undulate,  thin,  grayish  furfuraceous 
especially  beneath,  tardily  glabrate;  flowers  monoecious,  in  small  glomerules  of  the  mid- 
dle and  upper  axils,  the  upper  glomerules  mostly  or  entirely  staminate  but  a  few  stami- 
nate  flowers  often  in  the  lower  clusters  also;  perianth  of  4  or  5  sepals  in  the  staminate 
flowers,  wanting  in  the  pistillate;  fruiting  bracts  sessile  or  on  very  short  stalks,  scarcely 
compressed,  united  to  the  summit,  broadly  cuneate,  truncate  at  summit,  2  to  3  mm.  long, 
2  to  3  mm.  broad,  the  green  margins  developed  only  across  the  summit  and  here  with  2 
to  4  minute  teeth,  the  faces  smooth  or  rarely  with  1  or  2  minute  tubercles,  the  scurf 
obscure  and  the  veins  and  reticulations  prominent;  seed  1  to  1.5  mm.  long,  light  brown 


A.    TRUNCATA.  277 

to  dark  amber,  shining;    radicle  superior.     (Obione  truncata  Torrey,  in  Watson,  Bot. 
King's  Expl.  291,  1871.) 

Great  Basin  of  western  North  America  and  adjacent  territory;  Montana  to  eastern 
Colorado,  northwestern  New  Mexico  (according  to  Standley),  eastern  California,  eastern 
Washington,  and  British  Columbia;  apparently  most  plentiful  in  Idaho.  Type  locahty, 
near  Carson  City  and  on  the  Truckee  River,  Nevada.  Collections :  Armstead,  southwest- 
ern Montana,  Hall  11502,  11562  (UC);  Bitter  Creek,  Green  River,  Wyoming,  Nelson 
8I4I  (Gr);  near  Fountain,  Geyser  County,  Wyoming,  Mearns  S170  (US);  Laramie, 
Wyoming,  Johnston  2333  (UC) ;  3  km.  east  of  Longmont,  Colorado,  not  common.  Hall 
11074  (UC);  Argo,  Denver,  Colorado,  Eastwood  70  (UC,  US,  minor  variation  1,  var. 
stricta  Gray) ;  Fish  Lake,  Utah,  Jones  5745  (Herb.  Jones,  NY,  UC,  US,  type  collection  of 
A.  subdecumbens  Jones,  minor  variation  2);  Salt  Lake  City,  Utah,  Jones  1306  (DS,  Gr, 
US);  Nevada:  San  Antonio  Desert,  Purpus  64I8  (UC,  US,  minor  variation  1,  variety 
stricta  Gray,  in  part);  Smoke  Creek,  Chiffiths  and  Hunter  509  (US);  tjqje  collections, 
near  Carson  City,  Anderson  40  (Gr,  NY)  and  northwestern  Nevada,  Bailey  987  (Gr); 
Sparks, /faZi  11025  (UC);  Palisade,  August,  1885,  Brandegee  (UC);  Wells,  Humboldt 
River  Y alley,  Hall  11035  (UC);  California:  Randsburg,  1913,  Brandegee  (UC);  Monache 
Meadows,  southern  Sierra  Nevada,  Purpus  3007  (UC,  minor  variation  2,  A.  subdecum- 
bens Jones);  Benton  Hot  Springs,  Mono  County,  Hall  11699  (UC);  Bridgeport,  Mono 
County,  Hall  11693  (UC) ;  Loyalton,  Sierra  County,  Eastwood  7859  (SF) ;  eastern  Oregon, 
E.  Hall  433  (Gr,  type  of  variety  stricta  Gray,  minor  variation  1);  Klamath  Agency,  Ore- 
gon, Walpole  2310  (NY,  US) ;  Alma,  Okanogan  County,  Washington,  Ebner  531  (NY, 
US);  Idaho:  Weiser,  September  20,  1919,  Hall  (UC);  Twin  and  Shoshone  Falls,  Nelson 
and  Macbride  1373  (DS,  Gr,  NY,  UC,  US,  minor  variation  1,  variety  stricta  Gray);  New 
Plymouth,  Canon  County,  Macbride  323,  715  (DS,  UC);  Pocatello,  Palmer  412  (Gr, 
NY,  UC,  US);  Leadore,  Hall  11507  (UC);  near  Egbert  Spring,  Douglas  County,  Wash- 
ington, Sandberg  and  Leiberg  372  (SF,  UC) ;  Donald,  British  Columbia,  August  10,  1890, 
Macoun  (Gr).  Additional  localities,  mostly  represented  by  specimens  in  the  Rocky 
Mountain  Herbarium,  are  Rawhns,  Poison  Spider  Creek,  Point  of  Rocks,  Huttons  Lake, 
Sheridan,  Howell  Lakes,  Green  River,  Laramie  River,  and  Granger  in  Wyoming; 
Windsor,  Fort  CoUins,  Boulder  County,  and  Delta  in  Colorado;  Marysvale  and  Gunnison 
in  Utah;  Wadsworth  in  Nevada;  and  Silver  Lake,  lone,  and  Morrow  County  in  Oregon. 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Atriplex  truncata  var.  stricta  Gray,  Proc.  Am.  Acad.  8:  398,  1872. — Described  from  eastern  Oregon 
plants  as  follows:  foliis  hastato-lanceolatis  nunquam  cordatis,  inferioribus  basi  cuneatis;  inflorescentia  virgata 
minus  foliata.  This  is  an  occasional  development  that  appears  at  widely  separated  stations  (e.  g.,  Denver, 
Colorado,  Eastwood  70,  UC).  Therefore  it  is  doubtless  an  ecad.  Perfectly  simple-stemmed  and  rigidly  erect 
plants  are  sometimes  found,  but  along  with  them  grow  others  with  a  few  erect  branches  from  the  base.  Along 
Green  River,  in  Utah,  the  strict  form  grows  on  bottom-lands  where  partly  shaded. 

2.  A.  SUBDECUMBENS,  Jones  Proc.  Calif.  Acad.  II,  5:716,  1895. — Plants  low,  branched  from  the  base  and 
the  short  branches  subdecumbent;  leaves  only  0.5  to  1.5  cm.  long,  mostly  rounded  or  narrowed  to  the  base. 
Type  locality,  Fish  Lake,  Utah,  2,750  m.  altitude  in  gravelly  meadows  [Jones  S746).  The  extreme  of  this 
form  is  strikingly  different  from  the  rigidly  erect  plants  characteristic  of  true  truncata,  but  the  difference  is 
scarcely  greater  than  between  the  extremes  of  A.  cordulata  or  even  of  A.  argentea  (compare  the  minor  variation 
of  the  latter  listed  as  variety  hillmani).  The  small  narrow  leaves  are  remarkable,  but  even  in  the  type  collec- 
tion some  are  ovate  from  a  broad  base  which  is  abruptly  narrowed  to  a  petiole.  Still  broader  leaves  are  found 
on  plants  in  which  the  habit  is  decidedly  decumbent  (Monache  Meadows,  California,  Purpus  3007,  UC).  In- 
termediate, both  in  habit  and  foliage  are:  Randsburg,  California,  1913,  Brandegee  (UC);  Palisade,  Nevada, 
August,  1885,  Brandegee  (UC).  Prostrate  and  erect  plants,  both  with  subhastate  leaves,  sometimes  grow 
together  (Leadore,  Idaho,  Hall  11507,  UC).  Decumbent  plants  are  produced  by  injury  to  the  main  stem,  as  by 
grazing  (Bridgeport,  California,  Hall  1169S,  UC). 

3.  Obione  truncata  Torrey,  in  Watson,  Bot.  King's  Expl.  291,  1871.— A.  truncata.' 


278 


GENUS   ATRIPLEX. 


RELATIONSHIPS. 

Atriplex  truncata  is  closely  related  to  A.  argentea.  The  fruiting  bracts  have  undergone 
a  greater  reduction  in  size  and  the  free  herbaceous  margins  have  almost  disappeared. 
The  latter  are  represented  by  only  a  narrow  and  minutely  dentate  fringe  across  the 
summit.  The  strictly  cuneate  shape  is  quite  different  from  anything  known  in  argentea. 
In  some  specimens  of  the  latter  the  margins  of  the  bracts  are  so  greatly  reduced  as  to 
produce  an  appearance  similar  to  the  bracts  of  truncata,  but  the  shape  of  the  body,  the 
size,  and  the  foliage  still  indicate  the  form  as  only  a  deviation  from  true  argentea  (e.  g., 
Hanford,  California,  Kearney  154  US).  The  connection  with  A.  wolfi  will  be  con- 
sidered later  (p.  279). 


Fio.  35. — Phylogenetic  chart  of  the  Atriplex  truncata  group. 
ECOLOGY  AND  USES. 

Atriplex  truncata  resembles  the  other  vigorous  annuals  of  the  genus  in  ecological  beha- 
vior. It  is  primarily  a  halophyte,  often  growing  in  depressions  white  with  alkali,  where  it 
is  associated  with  Distichlis  and  Chrysothamnus  n.  consimilis,  or  it  may  occur  in  less 
alkaline  soil  with  Sporobolus  airoides.  The  range  as  to  the  salt-content  of  the  soil  is  from 
about  0.2  to  3  per  cent.  It  is  most  vigorous  in  low  salt-contents,  becoming  dwarfed  in 
soils  with  high  amounts.  In  consequence  it  readily  invades  fallow  fields  and  disturbed 
soils  of  low  alkalinity,  where  it  often  forms  a  stage  of  the  subsere.  It  is  exceptional 
among  related  annuals  in  ranging  to  9,000  feet  in  the  mountains  of  Utah,  and  nearly  as 
high  in  those  of  California  as  the  depressed  form,  subdecumbens.  It  blooms  early  in  the 
summer,  and  usually  sets  fruit  by  the  middle  of  July. 

In  spite  of  its  ruderal  habit,  this  species  never  becomes  a  serious  weed.  It  is  grazed 
throughout  its  range,  but  furnishes  a  considerable  amount  of  forage  only  in  restricted 
localities. 


A.    WOLFI — A.    GRACILIFLORA.  279 

18.  ATRIPLEX  WOLFI  Watson,  Proc.  Am.  Acad.  9:112,  1874.     Plate  42. 

Erect  annual  herb,  1  to  2  dm.  high,  branched  from  the  base  to  form  an  obpyramidal 
ramose  plant;  branches  ascending  or  spreading,  very  slender,  tough,  scurf y-canescent, 
glabrate,  turning  reddish  with  age;  leaves  alternate,  except  1  or  2  lower  pairs,  numerous, 
sessile,  linear  or  the  lowest  oblong-linear,  obtuse  or  acutish  at  apex,  0.5  to  1.5  cm.  long, 
0.1  to  0.2  cm.  wide,  entire,  thin,  pale  gray  with  a  dense  fine  scurf,  1-nerved,  often  condu- 
plicate;  flowers  monoecious,  all  axillary,  the  two  kinds  mixed  in  some  of  the  axils  but  the 
staminate  mostly  toward  the  ends  of  the  branches;  perianth  of  staminate  flowers  5-cleft, 
wanting  in  the  pistillate  flowers;  fruiting  bracts  sessile  or  subsessile,  compressed,  united 
to  the  summit,  cuneate-oblong,  truncate  and  with  3  minute  teeth  at  summit,  1.5  to  2  mm. 
long,  about  2  mm.  broad,  the  faces  either  smooth  or  with  a  few  minute  scattered  tubercles, 
the  veins  obscured  by  the  scurf;  seed  1.5  mm.  long,  pale  brown;  radicle  superior. 

Southern  Wyoming,  Colorado,  and  Utah.  Type  locality,  alkaline  flats  at  Saguache, 
central  Colorado.  Collections:  Fort  Steele,  southwestern  Wyoming,  Tweedy  4496  (NY); 
type  collection,  September,  1873,  l^o//and  Rothrock  £77  (Gr,  NY) ;  North  Park,  Colorado, 
August  31,  1897,  Osterhout  (R);  Grand  Junction,  Colorado,  May,  1891,  Eastwood  (UC); 
Gunnison,  Utah,  1,600  m.  altitude,  Jones  6525  (US);  Circle  Valley,  Utah,  2,140  m.  alti- 
tude, Jones  5987  (NY,  UC,  US).  Other  localities  represented  by  collections  in  the  M. 
E.  Jones  Herbarium,  Salt  Lake  City,  are  Green  River,  Wyoming;  Marysvale,  Utah;  and 
Ortons,  Utah. 

RELATIONSHIPS. 

Atriplex  wolfi  is  nearest  to  A.  truncata,  notwithstanding  its  very  different  appearance. 
The  fruiting  bracts  are  almost  exact  miniatures  of  some  found  on  this  species.  Reduc- 
tion has  taken  place  also  in  the  size  and  shape  of  the  leaf  and  in  the  suppression  of  the 
petiole.  The  dainty  habit  and  the  small  bracts  suggest  a  connection  with  the  pusilla 
group,  and  possibly  it  represents  the  beginning  of  this  line.  It  is  unlikely,  however, 
that  after  a  hne  had  once  developed  the  unusual  shape  of  bract  so  familiar  in  truncata 
and  in  this  species,  there  should  be  a  reversion  to  the  common  type  found  in  the  Pusillae. 
Moreover,  this  group  seems  to  have  originated  by  an  entirely  different  route,  namely, 
through  argentea  and  cordulata,  as  pointed  out  under  the  latter  species.  Whatever  its 
origin,  A.  wolfi  is  now  much  restricted  in  its  distribution  and  is  not  giving  rise  to  new 
forms.  Apparently  it  is  especially  adapted  to  peculiar  conditions  which  it  finds  only  in 
the  easterly  part  of  the  Great  Basin.  It  is  probably  much  more  common  and  occurs  over 
a  larger  area  than  is  indicated  by  the  specimens  cited,  for  the  plants  are  small,  delicate, 
short-lived,  and  easily  overlooked  by  collectors. 

ECOLOGY  AND  USES. 

Atriplex  wolfi  occurs  as  a  short-lived  annual  in  saline  areas,  usually  in  the  j4.  confertifolia 
consociation,  often  forming  pure  communities,  but  usually  mixed  with  Salsola,  and  on 
lower  areas  with  Suaeda.     It  is  too  delicate  to  be  of  value  for  grazing. 

19.  ATRIPLEX  GRACILIFLORA  Jones,  Proc.  Calif.  Acad.  II,  5:717,  1895.  Plate  42. 
Erect  annual  herb,  1  to  3  dm.  high,  widely  branched  from  the  base  and  also  somewhat 
above,  forming  a  flat-topped  or  more  rounded  plant  2  to  6  dm.  across;  branches  curved- 
ascending,  slender,  brittle,  not  angled,  sparsely  furfuraceous,  early  glabrate,  the  bark 
then  smooth  and  greenish-white;  leaves  alternate,  except  a  few  of  the  lowermost,  all 
distinctly  petioled,  cordate-ovate  or  deltoid-ovate,  cordate  or  broadly  truncate  at  base, 
obtuse  or  acutish  at  apex,  1  to  2  cm.  long  exclusive  of  petiole,  0.8  to  1.6  cm.  wide,  entire, 
fleshy  but  drying  thin,  greenish,  the  scurf  sparse,  the  veins  evident;  flowers  monoecious, 
the  staminate  glomerules  on  short  dense  branches  of  terminal  panicles,  the  pistillate  all 
axillary  (the  plants  fructiferous  almost  from  the  base);  perianth  of  staminate  flowers 


280  GENUS   ATRIPLEX. 

5-cleft  (as  far  as  known),  wanting  in  the  pistillate;  fruiting  bracts  long-  or  short-stalked 
or  sessile,  compressed,  united  to  the  summit,  the  body  elliptic,  but  the  whole  bract 
orbicular  through  the  development  of  marginal  wings  wider  than  the  body,  or  these 
margins  developing  only  above  and  the  bract  then  oblong,  10  to  16  mm.  long  and  broad, 
entire  or  undulate,  the  sides  seldom  appendaged,  very  sparsely  scurfy,  the  midvein  prom- 
inent and  the  reticulations  of  the  margins  sometimes  evident ;  seed  3  mm.  long,  dull- white ; 
radicle  superior. 

Known  only  from  Utah.  Type  locality,  Blue  Valley,  near  the  Henry  Mountains. 
Collections,  all  in  Utah:  type  collection,  1,220  m.  altitude,  in  clay,  July  30,  1894,  Jones 
5697  (Herb.  Jones,  NY,  R);  Cainville,  1,370  m.  altitude,  Jones  5656e  (according  to  Jones, 
1.  c.) ;  Price,  September,  1888,  Jones  (Herb.  Jones,  many  of  the  bracts  with  wings  nar- 
rowed below  the  middle) ;  near  Moab,  June  16,  1913,  Jones  (Gr) ;  Emery,  2,140  m.  altitude, 
Jones  5US  (UC);  foot  of  Book  Cliffs,  16  km.  north  of  Green  River,  Hall  110^2  (UC); 
near  Bear  Creek  ranger  station,  Manti  Forest,  Utah,  Willey  284.  (District  Forest  Herb. 
Ogden). 

RELATIONSHIPS. 

This  species  is  too  little  known  to  justify  positive  statements  as  to  its  phylogeny. 
Jones  has  suggested  a  rank  close  to  A.  canescens,  probably  because  of  the  remarkable 
wings  to  the  bracts.  But  these  wings  are  only  expansions  of  the  margins  and  there  are 
no  additional  wing-like  outgrowths  from  the  middle  line  of  each  bract,  as  occurs  in 
canescens.  The  herbaceous  and  monoecious  habit,  as  well  as  all  features  of  foliage  and 
flowers,  also  indicates  an  absence  of  any  direct  connection.  The  shape  of  the  bracts  is 
very  similar  to  that  of  A.  elegans,  but  otherwise  these  two  are  very  unlike. 

A.  graciliflora  is  more  probably  an  offshoot  from  the  argentea-truncata-saccaria  line 
and  is  now  restricted  to  peculiar  soils  where  no  other  species  can  grow.  Thus,  it  has 
become  a  relict  without  direct  connections.  It  is  more  like  saccaria  than  any  of  the  other 
species,  the  similarity  in  habit,  foliage,  and  inflorescence,  being  very  close.  Even  the 
fruiting  bracts  are  similar  in  shape  when  the  wing  fails  to  develop  in  graciliflora.  How- 
ever, even  under  these  conditions  the  bracts  are  never  strictly  cuneate  and  they  do  not 
have  the  narrow  terminal  border  of  that  species.  The  seed  especially  is  unlike,  being 
much  larger  and  pale  in  color,  a  peculiarity  that  distinguishes  graciliflora  also  from 
all  other  members  of  its  group. 

ECOLOGY  AND  USES. 

Atriplex  graciliflora  resembles  A.  saccaria  so  closely  that  it  appears  to  be  a  recent  and 
local  development  of  this,  which  has  retained  the  vegetative  structure  and  ecologic  habits 
practically  in  their  entirety.  It  forms  small  famiUes  in  clay  soils,  and  hence  regularly 
grows  in  the  Mancos  and  Mesa  Verde  shales  of  eastern  Utah,  where  it  behaves  essentially 
like  saccaria  in  habit  and  grouping.     This  species  has  no  uses. 

20.  ATRIPLEX  SACCARIA  Watson,  Proc.  Am.  Acad.  9:112,  1874.     Plate  43.     Twoscale. 

Erect  annual  herb,  1  to  3  or  5  dm.  high,  copiously  branched  throughout  to  form  a 
dense  globoid  bushy  plant;  branches  stout,  angled,  roughly  furfuraceous,  glabrate  only 
at  the  end  of  the  season,  the  bark  then  white  and  cracking  into  flakes;  leaves  mostly 
alternate,  all  decidedly  petiolate  or  the  upper  ones  subsessile,  broadly  cordate-ovate  or 
subreniform,  cordate  or  some  only  broadly  truncate  at  base,  acute  at  apex,  1  to  3  cm. 
long  exclusive  of  petiole,  1  to  2.5  cm.  wide,  entire,  thick  when  fresh  but  drying  thin,  gray 
or  nearly  white  with  a  rough  scurf,  rarely  glabrate,  the  veins  and  reticulations  prominent; 
flowers  monoecious,  the  staminate  glomerules  in  the  upper  axils  and  in  open  terminal 
panicles  (these  often  lost  in  mature  plants),  the  pistillate  all  axillary;  perianth  of  stam- 


A.    SACCARIA.  281 

inate  flowers  (always?)  5-cleft,  wanting  in  the  pistillate;  fruiting  bracts  long-stalked 
to  sessile,  scarcely  compressed,  united  to  the  summit,  of  two  kinds,  the  smaller  (normal?) 
ones  cuneate,  truncate  at  summit,  3  mm.  long  and  nearly  as  broad,  margined  only  at 
summit,  the  margin  here  undulate  or  with  a  few  minute  teeth,  the  sides  smooth,  the  larger 
bracts  (often  in  the  same  axils,  sometimes  scarce  or  reduced,  as  in  the  type),  globoid 
through  the  development  of  numerous  appendages,  up  to  6  mm.  in  diameter,  thickly 
beset  with  flat  or  cristate  appendages  or  some  of  these  horn-like,  all  of  the  bracts  densely 
scurfy  and  the  veins  not  prominent;  seed  1.8  to  2.3  mm.  long,  brown;  radicle  superior. 
Middle  and  southerly  parts  of  the  Great  Basin,  in  the  warmer  districts,  in  strongly 
alkaline  clay  soils ;  southwestern  Wyoming  and  northern  Utah  to  southwestern  Colorado, 
western  Texas,  northern  Arizona,  and  southern  Nevada.  Type  locality,  on  the  desert 
plains  of  southern  Wyoming  or  northern  Utah.  Collections:  Fort  Bridger,  Wyoming, 
July,  1873,  Porter  (Or);  type  collection,  "Wyoming-Nevada  deserts,"  1872,  Gray  (Gr); 
Marysvale,  Utah,  June  5,  1894,  Jones  (UC) ;  along  San  Juan  River,  near  Bluffs,  Utah, 
Rydberg  and  Garrett  9930  (NY,  US);  Green  River,  Utah,  Jones  5481  (Herb.  Jones,  type  of 
A.  cornuta  Jones,  minor  variation  2);  near  San  Rafael  River,  Utah,  Hall  IIO4O  (UC); 
Naturita,  southwestern  Colorado,  Payson  2327  (UC);  El  Paso,  Texas,  September  10, 
1884,  Jones  (Gr);  Ojo  Alamo,  San  Juan  County,  New  Mexico,  Hall  11134  (UC) ;  Billings, 
Arizona,  October  8,  1884,  Jones  (Herb.  Jones);  Chalcedony  Park,  first  and  second  petri- 
fied forests,  Arizona,  Hall  11155,  11163  (UC);  Las  Vegas,  southern  Nevada,  June,  1915, 
Brandegee  (UC);  Caliente,  southern  Nevada,  August  27,  1912,  Jones  (UC).  Additional 
localities  represented  by  specimens  in  the  Jones  Herbarium  at  Salt  Lake  City  are  the 
following,  all  in  Utah:  Marvine,  Myton,  Westwater. 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Atriplex  argentea  var.  cornuta  Jones,  Contr.  West.  Bot.  11:  21,  1903.— This  is  merely  a  reduction 
of  the  earlier  A.  cornuia.  The  suggested  connection  with  A.  argentea  can  not  be  accepted,  since  the  bracts, 
when  not  modified  by  appendages,  are  plainly  of  the  truncata  type  and  not  at  all  like  those  of  argentea.  (See 
under  cornuta  of  this  list.) 

2.  A.  CORNUTA  Jones,  Proc.  Calif.  .4cad.  II,  5:  718,  1895. — This  is  exactly  the  .same  as  A.  saccaria,  as  deter- 
mined after  an  earlier  comparison  of  the  types,  except  that  the  fruiting  bracts  are  covered  with  long  appendages. 
Complete  type  material  of  cornuia  is  not  at  hand  at  this  writing,  but  in  specimens  from  the  type  locality,  and 
indicated  by  Jones  as  cornuta  (Green  River,  May  23,  1895),  the  bracts  vary  from  large  and  bur-like,  as  described 
for  cornuta,  to  narrow,  cuneate,  and  smooth-faced.  The  presence  of  these  cuneate  bracts  indicates  very 
clearly  that  cornuta  is  the  same  as  saccaria  and  that  both  have  a  connection  with  truncata  rather  than  with 
argentea.  Jones  once  reduced  his  species  to  a  variety  of  the  latter,  but  aside  from  the  character  just  mentioned, 
it  differs  also  in  the  cordate  leaves  and  in  the  constantly  better  development  of  the  staminate  inflorescence. 

3.  A.  EXPANSA  CORNUTA  Standley,  N.  Am.  Fl.  21:45,  1916,  as  synonym.  This  combination  was  due 
merely  to  an  oversight.     The  combination  intended  by  Jones  is  the  one  given  under  No.  1  of  this  list. 

4.  A.  TRUNCATA  var.  SACCARIA  Jones,  Contr.  West.  Bot.  1 1 :  20,  1903. — The  reduction  is  made  without 
comment.    The  reasons  for  retaining  saccaria  in  specific  rank  will  be  given  under  Relationships. 

RELATIONSHIPS. 

Either  this  species  is  a  direct  development  from  A.  truncata,  or  the  two  have  evolved 
from  a  common  stock  after  this  had  become  separated  from  all  other  Atriplexes.  This 
conclusion  results  from  the  close  similarity  in  normal  fruits.  In  the  present  species 
these  fruiting  bracts  often  are  so  densely  covered  with  long,  horn-like  projections  and 
cristate  outgrowths  that  their  original  or  primitive  shape  is  entirely  hidden.  However, 
other  bracts  can  be  found,  usually  if  not  always  on  the  same  plant,  which  have  not 
developed  these  appendages,  and  such  bracts  are  practically  identical  with  those  of 
truncata.  The  peculiar  cuneate  shape  occurs  nowhere  in  the  genus  outside  of  the  truncata 
group.  The  reduction  of  the  free  margin  to  a  very  narrow  border  across  the  truncate 
summit  also  is  unique.  On  the  other  hand,  the  differences  between  A.  saccaria  and 
A.  truncata  are  sufficient  to  justify  the  retention  of  both.     The  former  never  assumes 


282  GENUS   ATEIPLEX. 

the  open,  strict  habit  of  the  latter;  the  leaves  are  for  the  most  part  cordate  at  base, 
always  much  broader  in  proportion  to  their  length  and  hence  more  rounded-ovate; 
the  staminate  glomerules  are  always  in  well-developed,  open,  naked,  graceful  terminal 
panicles,  instead  of  sessile  in  the  upper  axils,  as  they  are  in  truncala. 

A  reduction  to  A.  argentea  has  been  suggested,  as  noted  under  the  minor  variations. 
But  the  differences  here  are  even  greater,  for  in  addition  to  those  just  indicated  as 
separating  saccaria  from  truncala,  the  normal  fruiting  bracts  are  very  unlike  in  shape 
and  in  the  development  of  the  free  margins.  However,  there  is  a  minor  variation  of 
argentea  (caput-medusae)  in  which  the  bracts  develop  remarkably  large  appendages 
similar  to  those  common  in  saccaria.  Probably  it  was  a  comparison  of  plants  in  this 
condition  that  led  to  the  taxonomic  reduction  just  mentioned.  The  unappendaged 
bracts  here  furnish  the  dependable  clue  as  to  relationships,  although  the  leaf  and  inflor- 
escence characters  also  enable  one  to  distinguish  saccaria  and  argentea  with  certainty. 
It  should  here  be  noted  that  the  latter  occasionally  develops  an  elongated  staminate 
inflorescence.  This,  however,  is  rigid  and  spike-like,  as  compared  with  the  slender, 
curving  panicle  of  saccaria. 

The  original  description  of  A.  saccaria  gives  the  bracts  as  "not  at  all  appendaged." 
This  was  due  to  an  oversight,  for,  while  most  of  the  bracts  on  the  type-sheet  are  not 
appendaged,  others,  often  in  the  same  axils,  bear  a  few  appendages. 

ECOLOGY  AND  USES. 

Atriplex  saccaria  is  the  most  typical  indicator  of  bad-land  shales.  It  is  usually  the 
first  and  often  the  pioneer  in  rillways  and  on  the  many  small  fans  in  Bad  Lands,  and  not 
infrequently  forms  families  on  the  crumbling  slopes.  The  plants  are  typically  low,  com- 
pactly branched,  and  closely  aggregated,  both  habit  and  grouping  significant  of  the  extreme 
xerophytic  conditions  and  the  precarious  foothold.  The  salt-content  usually  ranges 
from  1  to  2  per  cent,  but  is  often  much  higher.  In  more  stable  spots  this  species  is 
usually  associated  with  A.  dioeca  or  Eriogonum  divaricatum.  In  ecological  response  it 
is  practically  identical  with  A.  graciliflora,  due  to  the  fact  that  both  grow  in  the  same  type 
of  habitat. 

This  plant  has  rarely  been  found  to  be  grazed,  probably  because  of  its  high  salt-content. 

21.  ATRIPLEX  ARGENTEA  NuttaU,  Genera  1 :  198, 1818.     Plates  43  and  44.     Silverscale. 

Erect  annual  herb,  1.5  to  8  dm.  high,  freely  branched  from  the  base  and  globoid  in 
outline,  or  rarely  with  few  branches  and  more  strict ;  branches  stout,  angled,  f urf uraceous 
when  young,  the  whitish  bark  exfoliating  in  age;  leaves  alternate  except  the  lowermost 
ones,  sessile  or  subsessile  or  the  lower  ones  decidedly  petiolate,  lanceolate,  ovate  or  deltoid, 
2  to  5  cm.  long  (exclusive  of  petiole),  1  to  4  cm.  wide  (smaller  in  minor  variation  1), 
cuneate  to  subhastate  at  base  (all  narrowed  to  the  base  only  in  minor  variation  9,  A. 
rydbergi  Standley),  mostly  obtuse  or  only  slightly  acute  at  apex,  entire  or  repand-dentate, 
not  exceptionally  thickened,  grayish-furfuraceous,  glabrate;  flowers  monoecious,  in 
axillary  glomerules  and  in  terminal  interrupted  spikes,  the  staminate  and  pistillate 
flowers  usually  mixing  in  the  clusters,  but  the  former  mostly  toward  the  ends  of  the 
branches  and  sometimes  forming  purely  staminate  spikes;  perianth  of  4  to  5  sepals  in 
the  staminate  flowers,  wanting  in  the  pistillate;  fruiting  bracts  sessile  or  subsessile, 
more  or  less  compressed,  united  to  the  middle  or  above,  obovate  or  cuneate-orbicular, 
4  to  8  mm.  long,  4  to  10  mm.  wide,  including  the  green  foliaceous  margins,  which  are 
subentire  to  variously  laciniate,  the  faces  smooth  or  appendaged  or  crested;  seed  1.5 
to  2  mm.  long,  brown;  radicle  superior. 

Abundant  in  moderately  alkaline  soils  of  western  North  America  and  northern  Mexico; 
southern  Saskatchewan  to  western  Texas,  northern  Chihuahua,  California,  and  Idaho. 


A.    ARGENTEA.  Z»d 

SUBSPECIES. 

The  characters  of  this  species  are  subject  to  a  wide  range  of  variation,  and  it  exhibits 
in  consequence  a  considerable  series  of  striking  forms.  This  has  led  to  the  naming 
of  9  species  and  varieties  segregated  from  what  is  here  included  under  A.  argentea. 
The  characters  used  as  bases  for  these  segregates  are  themselves  so  variable  and  occur 
in  so  many  combinations  that  many  times  this  number  would  need  to  be  accepted  if 
one  were  to  recognize  all  of  the  forms  as  they  occur  in  the  field.  However,  by  the  utiliza- 
tion of  the  features  that  seem  to  possess  the  greatest  phyletic  value,  two  principal 
stocks  or  subspecies  may  be  distinguished.  Other  forms  are  better  treated  as  minor 
variations. 

Key  to  the  Subspecies  of  Atriplex  argentea. 

Upper  leaves  short-petioled  or  subsessile.     Distribution  easterly  from  Nevada (a)  typica     (p.  283) . 

Upper  leaves  closely  sessile.     California  to  Texas (6)  expansa  (p.  284). 

21a.  Atriplex  argentea  typica. — Leaves  all  more  or  less  petioled,  the  petiole  from 
nearly  as  long  as  the  blade  on  lower  leaves  to  almost  obsolete  on  upper  ones;  blades 
triangular-ovate  or  rounded-ovate,  often  subhastate.  {A.  argentea  Nuttall,  1.  c.)  In 
moderately  alkaline  soil,  Saskatchewan  to  North  Dakota,  northern  New  Mexico,  Nevada, 
northeastern  California,  eastern  Oregon,  and  Idaho;  also  east  to  the  Mississippi  River, 
perhaps  as  an  introduction.  Type  locality,  on  sterile  and  saline  places  near  the  Missouri 
River.  Collections:  Southern  Saskatchewan,  Macoun  1496  (US);  Glendive,  Montana, 
September  2,  1892,  Sandberg  (DS,  UC);  Yellowstone  Valley,  Montana,  August  19, 
1898,  Setchell  (UC);  Iroquois,  South  Dakota,  August  11,  1894,  Thornber  (Gr,  NY,  UC); 
eastern  Pennington  County,  South  Dakota,  Over  1816  (US,  minor  variation  2,  A.  caput- 
medusae  Eastwood);  Upper  Louisiana,  Nuttall  (Phila,  "Pursh's  specimen,  ex-herb.  Lam- 
bert"); Wyoming:  Middle  Fork  Powder  River,  Johnson  County,  Nelson  270  (UC); 
Seven-Mile  Lake,  Nelson  2796  (R,  type  of  A.  volutans  Nelson,  minor  variation  11); 
Fisher's  Ranch,  Nelson  5319,  5820  (UC) ;  Altamont,  extreme  southwest,  Johnston  2335 
(UC) ;  Albany  County,  Nelson  8166  (Gr,  NY,  US) ;  5  km.  east  of  Longmont,  northeastern 
Colorado,  not  common.  Hall  11075  (UC);  near  Clear  Creek  and  Sloans  Lake,  Denver, 
Colorado,  Eastwood  54,  104  (UC);  Canon  City,  Colorado,  September,  1873,  Brandegee 
(UC) ;  Grand  Junction,  southwestern  Colorado,  Baker  927  (Gr,  UC,  US) ;  Kiowa  Valley, 
western  Nebraska,  Rydberg  325  (US,  NY);  salt-marsh,  Lincoln,  Nebraska  (introduced?), 
September,  1890,  Rydberg  (US);  Syracuse,  Kansas  (introduced?),  Thompson  145  (Gr, 
US);  San  Juan  River,  Utah,  Eastwood  116  (Gr,  US,  type  collection  of  A.  caput-medusae 
Eastwood,  minor  variation  2);  Aztec  ruins,  northwestern  New  Mexico,  Hall  11125 
(UC,  same  variation);  south  of  Shiprock  Station,  northwestern  New  Mexico,  Hall  11145 
(UC,  same  variation);  Navajo  Indian  Reservation,  northeastern  Arizona,  Standley 
7446  (US);  Winslow,  northern  Arizona,  Hall  11175  (UC);  Caliente,  southern  Nevada, 
August  7,  1912,  Jones  (DS);  just  east  of  Reno,  Nevada,  August  11,  1894,  Hillman 
(Herb.  Jones,  type  of  A.  argentea  hilhnani,  minor  variation  1);  Peavine,  western  Nevada, 
July,  1913,  Brandegee  (UC,  same  variation);  Truckee  River  near  Vista,  Nevada,  Hall 
11027  (UC,  same  variation);  Sierra  Valley,  northeastern  California,  Lenunon  1206  (Gr, 
same  variation);  Malheur  County,  Oregon,  Cusick  1263  (Gr,  US);  Pocatello,  Idaho, 
Palmer  536  (US). 

Additional  localities  in  Nevada  are  cited  under  minor  variation  1.  Other  stations 
represented  mostly  by  specimens  at  the  Rocky  Mountain  Herbarium  include  north- 
western Harding  County  and  Fall  River  County  in  South  Dakota;  Hanna,  Gardiner 
River,  Meadow  Creek,  Sheridan,  Buffalo,  Douglas,  Glendo  (Laramie  County),  Big 
Laramie  River,  Newcastle  (Weston  County),  and  Howell  Lakes  in  Wyoming;  Windsor, 


284  GENUS   ATRIPLEX. 

Fort  Collins,  Pueblo,  and  Grand  Junction  in  Colorado;  Chadron  in  Nebraska;  Wyandotte 
(rare,  introduced)  and  Logan  County  in  Kansas;  Amedee  in  California;  and  Genoa  in 
Nevada. 

216.  Atriplex  arqentea  expansa  (Watson). — Lower  leaves  on  petioles  sometimes 
as  long  as  the  blade,  the  middle  and  upper  leaves  closely  sessile,  commonly  erect  or 
incurved  through  the  axils;  blades  broadly  cordate-ovate  to  lance-ovate,  often  sub- 
hastate  but  the  lower  sometimes  tapering  to  the  petiole.  {A.  expansa  Watson,  Proc. 
Am.  Acad.  9:116,  1874.)  In  alkaline  and  often  in  fallow  soil,  northern  Mexico  to 
Arizona  and  CaUfornia,  most  abundant  in  western  Texas,  southern  New  Mexico,  and 
California,  in  the  last-named  State  especially  on  alkaline  areas  of  the  coastal  slope  as 
far  north  as  the  region  of  San  Francisco,  and  in  the  interior  throughout  the  San  Joaquin 
Valley,  less  plentiful  in  the  Sacramento  Valley.  Type  locality,  not  definitely  stated, 
but  the  description  drawn  chiefly  from  specimens  collected  in  the  valley  of  the  Rio 
Grande,  western  Texas.  Collections:  Valley  of  the  Rio  Grande,  Paso  del  Norte, 
Chihuahua,  Pringle  1996  (Gr,  NY,  UC,  US);  "western  Texas  to  El  Paso,  New  Mexico," 
May  to  October,  1849,  Wright  (Gr,  one  of  the  types);  El  Paso,  Texas,  Jones  ^169j 
(Herb.  Jones);  Barstow,  western  Texas,  common,  Earle  631  (NY);  Mesilla  Valley, 
Dona  Ana  County,  New  Mexico,  October  5,  1889,  Wooton  (US);  California:  National 
City,  San  Diego  County,  July,  1902,  Brandegee  (UC);  Ramona,  San  Diego  County, 
October,  1903,  Brandegee  (UC);  San  Bernardino,  1891,  Parish  (UC);  Westminster, 
Orange  County,  September  10,  1901,  Byram  (UC) ;  Ballona  Lagoon,  coast  of  Los  Angeles 
County,  Chandler  2013  (UC) ;  Los  Angeles,  Braunton  138  (UC) ;  Oxnard,  Ventura  County, 
Davy  7822  (UC);  Carpenteria,  Santa  Barbara  County,  October  18,  1919,  Hall  (UC); 
Lancaster,  west  end  Mojave  Desert,  October  21,  1919,  Hall  (UC);  dried  bed  of  Kern 
Lake,  San  Joaquin  Valley,  Davy  2910  (UC);  west  of  McFarland,  Kern  County,  October 
24,  1919,  Hall  (UC);  Earlimart,  Tulare  County,  Hall  11785  (UC);  Hanford,  Kings 
County,  common  in  strongly  alkaline  soil,  September  28,  1901,  Kearney  (US);  south  of 
Corcoran,  Kings  County,  October  24,  1919,  Hall  (UC);  south  of  Merced,  very  common, 
October  25,  1919,  Hall  (UC);  Manteca,  San  Joaquin  County,  October  26,  1919,  Hall 
(UC);  fallow  field  at  Livermore,  Alameda  County,  Hall  10964  (UC);  Stockton,  Davy 
1190,  1191  (UC);  Brock  Lane,  near  the  Arequipa  Hills,  Solano  County,  September  22, 
1891,  Jepson  (Herb.  Jepson,  type  of  A.  trinervata  Jepson,  minor  variation  10);  west  of 
Norman,  Glenn  County,  Sacramento  Valley,  common,  Hall  11008  (UC). 

MINOR  variations  AND  SYNONYMS. 

A  discussion  of  the  value  of  the  characters  on  which  some  of  the  following  rest  will  be  found  under  the  heading 
of  Relationships. 

1.  Atriplex  argentea  hillmani  Jones,  Contr.  West.  Bot.  11:21, 1903. — This  is  a  geographic  form  or  race  of 
A.  argentea  lypica.  It  is  common  in  northern  Nevada,  southeastern  Oregon,  and  northeastern  CaUfornia.  The 
only  important  character  is  the  habit,  the  plants  being  low,  rarely  over  2  dm.  high,  although  the  branches  are 
sometimes  widely  spreading.  However,  this  trait  is  sometimes  constant  over  extensive  areas,  as,  for  example, 
in  the  valley  of  the  Humboldt  River,  especially  along  embankments.  This  variation  appaars  to  be  a  response 
to  the  more  arid  climate  of  those  districts,  which  has  left  a  sufficient  impress  upon  the  plant  to  make  its  character 
more  or  less  permanent,  or  at  least  constant  for  that  area.  While  the  development  of  the  plant  is  the  most  strik- 
ing and  constant  character,  the  variety  hillmani  was  based  also  upon  other  features.  These  were  the  crested 
bracts  (which  recur  so  frequently  and  without  regularity  in  argentea  as  to  be  of  no  value  as  a  criterion),  together 
with  the  sessile  character  of  these.  It  is  only  this  last  feature,  and  perhaps  the  size  of  plant,  that  separates 
hillmani  from  caput-medu.iae  (No.  2  of  this  list),  but  this  character  has  been  demonstrated  to  be  much  too  variable 
to  be  of  significance.  The  following,  the  last  four  of  which  have  both  sessile  and  stalked  bracts,  the  sides  of 
which  are  both  smooth  and  appendaged  on  the  same  plant,  belong  to  this  form:  Nevada:  East  of  Reno,  August 
11,  1894,  Hillman  (Herb.  .Jones,  type);  English  Mill,  near  Reno,  July  11,  1893,  Hillman  (US);  Monitor  Valley, 
Waison  985  (Gr);  Leonard  Creek  Ranch,  northern  Nevada,  Griffiths  and  Morris  346  (US);  Battle  Mountain, 
Hitchcock  686  (US);  same  locality,  Kennedy  4001  (DS,  US);  Lemmon  Valley,  Washoe  County,  Kennedy  2081 
(DS,  US);  Sierra  Valley,  California,  Lemmon  1206  (Gr);  Malheur  County,  Oregon,  Casick  1263  (Gr,  US). 


A.    ARGENTEA,  285 

2.  A.  CAPUT-MEDUSAE  Eastwood,  Proc.  Calif.  Acad.  II,  6:316,  plate  46,  1896. — The  form  or  state  of  A.  argen- 
tea  typica  in  which  the  faces  of  most  of  the  fruiting  bracts  are  covered  with  flat,  horny,  acuminate,  and  often 
twisted  processes,  and  the  bracts  themselves  plainly  stalked.  Such  plants  are  especially  common  in  northern 
New  Me.xico,  but  field  studies  indicate  that  there  is  no  dividing-line  between  this  form  and  typica.  Tiie  vari- 
ability in  the  appendage  character,  also  in  the  length  of  the  stalks  to  the  bracts,  and  in  the  distribution  of  the 
flowers  is  now  well  known  (see,  for  example,  plates  43  and  44).  Similar  but  not  identical  bracts  are  sometimes 
encountered  also  in  subspecies  expansa.  The  type  locality  of  capid-medusae  is  near  Recapture  Creek,  along  the 
banks  of  the  San  Juan  River,  southwestern  Utah. 

3.  A.  EXPANSA  Watson,  Proc.  Am.  Acad.  9:116,  1874. — A.  argentea  expansa. 

4.  A.  EXPANSA  var.  mohavensis  Jones,  Contr.  West.  Bot.  11:20,  1903. — Differs  from  genuine  A.  argentea 
expansa  only  in  the  smaller  and  therefore  sharper  teeth  along  the  margins  of  the  practically  sessile  fruiting 
bracts.  Principally  Californian,  although  the  other  form  occurs  there  also.  Standley  has  added  the  smaller 
size  of  the  bracts  as  a  criterion  (N.  Am.  Fl.  21 :47,  1916).  All  of  these  differences  are  due  to  a  reduction  in  the 
width  of  the  herbaceous  border  in  many  Californian  plants,  so  that  the  teeth  are  smaller  and  therefore  seemingly 
more  acute.  These  far-western  specimens  have  bracts  which  are  also  more  uniformly  sessile  or  subsessile  and 
with  a  less  frequent  tendency  toward  the  formation  of  appendages.  But  as  to  dentation,  the  genuine  expansa 
type  of  bract  is  also  reproduced  in  western  California  on  plants  in  which  other  bracts  have  only  the  narrow, 
finely  dentate  border  (e.  g.,  Redondo,  Piemeisel  3706,  US),  and  conversely,  the  mohaven.ns  type  sometimes  occurs 
on  plants  from  New  Mexico  (Mesilla  Valley,  October  5,  1889,  Wooton,  US),  together  with  bracts  of  typical  ex- 
pa7isa.  These  conditions  are  illustrated  in  the  accompanying  plates  and  text-figures.  As  to  the  difference  in 
the  length  of  the  stalk,  it  need  only  be  said  that  the  large  series  of  specimens  from  Texas  and  New  Mexico  now 
in  herbaria  shows  sessile  about  as  often  as  stalked  bracts,  although  in  the  caput-medusae  type  they  are  usually 
long-stalked,  with  ordinary  sessile  ones  on  the  same  plant  (e.  g.,  Archer  County,  Texas,  Reverchon  823,  US). 
Type  locality  of  variety  mohavensis,  Mojave  region  to  San  Bernardino,  California. 


Fio.  36. — Fruiting  bracta  of  minor  variations  of  Atriplex  argentea  expansa:  a,  5,  e,  from  western  California  {Piemeiael  S708 
US) ;  d,  e,  /,  from  Mesilla  Valley,  New  Mexico  (Wooton  US) ;  a,  h,  i,  from  western  Texas  (Earle  631  NY).  All  X  2. 
(See  under  minor  variation  4.) 

5.  A.  EXPANSA  TRINERVATA  Macbride,  Contr.  Gray  Herb.  53:  9,  1918. — Based  upon  A.  trinervata,  which  see. 

6.  A.  HiLLMANi  Standley,  N.  Am.  Fl.  21 :48,  1916. — Based  upon  A.  argentea  hillmani,  which  see. 

7.  A.  MOHAVENSIS  Standley,  1.  c,  47. — Based  upon  A.  expansa  mohavensis,  which  see. 

8.  A.  NODOSA  Greene,  Pittonia  1:40,  1887. — A.  argentea  expansa.  An  insect-stung  monstrosity,  according 
to  Jepson  (Fl.  Calif.  436,  1914).  A  fragment  of  the  type  is  preserved  at  the  University  of  California.  It 
seems  to  be  a  common  form  of  expansa  in  which  the  long-stemmed  bracts  are  covered  with  prominent  append- 
ages, as  in  capul-medusae  (No.  2  of  this  list). 

9.  A.  RYDBERGi  Standley,  1.  c,  47. — A  striking  variation  which  perhaps  should  be  treated  as  a  distinct  sub- 
species, but  too  httle  known  and  the  distinguishing  characters  too  subject  to  fluctuation  to  warrant  a  final  dis- 
posal at  this  time.  The  leaves  are  all  cuneate  or  acute  at  the  base.  Such  leaves  sometimes  occur  in  true 
argentea,  but  always  mixed  in  with  a  larger  number  with  broad  bases.  The  staminate  glomerules  are  in  slender 
interrupted  spikes,  these  2  to  6  cm.  long.  Such  spikes  are  unusual  in  A.  argentea  typica.  They  occur,  however, 
in  some  specimens,  notably  one  from  near  Grand  Junction,  Colorado  {H all  11045).  In  this  the  leaves  are  exactly 
intermediate  (fig.  37,  d,  e,  f,  g).  Long,  staminate  spikes  develop  also  in  subspecies  expansa  (Westminster, 
Orange  County,  California,  June  20,  1896,  McClalchie,  UC).  The  type  specimen  of  rydbergi,  which  came  from 
southeastern  Utah,  is  young  and  but  few  of  the  lower  bracts  are  well  formed.  These  are  compressed,  flabelli- 
form,  the  margins  with  4  or  5  coarse  teeth,  the  sides  either  smooth  or  slightly  muricate.  They  suggest  A. 
powelli  in  shape,  but  lack  the  broad  entire  summit  of  that  species  and  the  leaves  have  an  entirely  different 
venation.     (See  fig.  37.) 

10.  A.  TRINERVATA  Jcpsou,  Pittoda  2:305,  1892. — A.  argentea  expansa,  but  the  large  leaves  irregularly 
toothed  and  strongly  3-nerved  from  the  base,  the  bracts  also  strongly  nerved.  The  large  size  of  the  leaves  is 
associated  with  vigor  of  growth  and  doubtless  is  responsible  in  turn  for  the  dentations,  which  are  seldom  pro- 
nounced and  never  regular.  All  plants  of  expansa  show  a  triple  nerving  of  the  leaves.  The  prominence  of  the 
nerves  is  exceedingly  variable  and  can  not  be  correlated  with  the  other  characters  enumerated.  Macbride 
(Contr.  Gray  Herb.  53:9,  1918)  recently  has  attempted  to  sustain  trinervata  in  varietal  rank,  calling  dis- 
tributional considerations  to  its  support.     But  contrary  to  his  assumption,  it  does  not  replace  typical  expansa 


ZW  GENUS   ATRIPLEX. 

in  central  and  northern  California  (where  the  entire-leaved  form  is  exceedingly  common),  and  on  the 
other  hand,  it  ranges  to  southern  California,  th?  best  example  of  large,  trinervate  and  dentate  leaves  coming 
from  southern  Santa  Barbara  County.  Furthermore,  the  bracts  in  the  type  specimen  are  united  well  above 
the  middle  and  most  of  them  are  short-stalked,  so  that  these  features  can  not  be  used  for  the  separation  of  tri- 
nervata.  It  seems,  therefore,  that  Jepson  was  correct  in  reducing  his  species  to  expansa  (Jepson,  Fl.  Calif.  437, 
1914)  and  that  it  represents  only  a  common  response  to  conditions  favorable  for  exceptional  growth.  Type 
locality,  near  the  Arequipa  Hills,  Solano  County,  California. 

11.  A.  VOLUTANS  Nelson,  Bull.  Torr.  Club  25:203,  1898.— The  more  globoid  robust  form  of  A.  argentea  typicu, 
as  indicated  by  Nelson  (Bot.  Gaz.  34:358,  1902).     Type  locality,  Seven-Mile  Lake,  Wyoming. 

12.  Obione  argentea  Moquin,  Chenop.  Enum.  76,  1840.—^.  argentea  typica. 


C 


37  38 

Fio.  37. — Minor  variations  of  Atriplex  argentea:  a,  b,  e,  from  the  type  ol  A.  rydbergi  (minor  variation  9);  d,  e,  /,  g,  a  form 

from  Grand  Junction,  Colorado,  intermediate  to  typical  argentea.     All  X  0.8. 

Fio.  38. — Alriplex  argentea  expanaa,  minor  variation  10  (A.  trinervata  Jepson):  a,  leaf,  X  1 ;  b,  c,  fruiting  bracts,  X  2.     Drawn 

from  the  type  specimen  (Herb.  Jepson). 

RELATIONSHIPS. 

This  is  looked  upon  as  the  central  species  of  a  large  group  that  has  progressed  beyond 
A.  dioeca,  A.  phyllostegia,  etc.,  in  a  number  of  characters,  but  especially  in  the  complete 
suppression  of  the  perianth.  Since  each  of  the  other  species  of  the  argentea  group  exhibit 
certain  specialized  features,  the  relation  between  them  and  argentea  will  be  discussed 
as  they  are  reached  in  the  sequence. 

There  are  here  included  within  the  species  a  considerable  number  of  forms,  certain  of 
which  represent  diverging  lines  of  development.  However,  all  of  the  variations  seem 
to  belong  to  two  principal  branches,  or  stocks.  These  are  treated  as  subspecies,  namely 
typica  and  expansa.  In  the  former,  even  the  upper  leaves  usually  exhibit  at  least  a  short 
petiole,  while  in  the  latter  the  upper  leaves  are  very  closely  sessile  and  the  blades  com- 
monly incurved  between  the  stems  (plate  44,  figs.  1,  6,  7).  The  two  are  not  widely 
separated  geographically,  but  typica  is  chiefly  a  Mississippi  Valley,  Rocky  Mountain,  and 
Great  Basin  form,  while  expansa  belongs  to  the  southern  borders  of  the  United  States 
and  to  California.  They  are  therefore  believed  to  be  geographic  types  which  are 
separating  in  their  morphologic  characters,  although  an  overlapping  along  the  boundaries 
has  prevented  a  complete  separation.  The  absence  of  a  complete  parallelism  between 
geographic  distribution  and  established  characters  is  evidenced  by  the  occasional  appear- 
ance of  plants  of  one  subspecies  well  within  the  area  assigned  to  the  other.     Examples 


A.    ARGENTEA. 


287 


are  specimens  of  typical  argentea  from  Antioch  and  San  Joaquin  County,  central  Cali- 
fornia (July  4,  1902,  Congdon,  Gr,  US;  Cusick  688,  Gr),  and  from  San  Bernardino, 
California  (August  20,  1893,  McClatchie,  NY);  also  specimens  of  expansa  from  north- 
eastern Utah  (C.  P.  Smith  2073,  DS,  SF). 

In  some  keys  and  descriptions  these  two  subspecies  are  also  differentiated  by  their 
lower  leaves,  these  being  described  as  opposite  in  typica,  alternate  in  expansa;  but  field 
studies  in  California  have  demonstrated  that  the  lower  leaves  of  expansa  also  are  opposite. 
This  finding  has  been  verified  by  garden  experiments  in  which  the  seedlings  from 
several  different  collections  of  seeds  had  uniformly  opposite  lower  leaves.  The  error 
as  to  the  arrangement  of  the  lower  leaves  doubtless  has  crept  into  the  literature  because 
of  the  incomplete  nature  of  most  herbarium  specimens.  Many  other  characters  used  in 
herbarium  segregation  of  supposedly  new  species  from  A.  expansa  are  now  found  to  be 
so  variable,  even  on  individual  plants,  that  they  can  no  longer  be  used.  Some  such  are 
almost  certainly  the  result  of  a  pathologic  condition. 

Especially  unreliable  features  are  those  that  have  to  do  with  the  "pedicels"  and 
sculpturing  of  the  fruiting  bracts.  The  former  are  of  course  only  modified  leaf-petioles 
and  their  length  is  therefore  subject  to  much  variation.  Long-stalked  and  sessile  bracts 
on  the  same  plant  is  a  common  occurrence.  The  former  condition  is  almost  constantly 
associated  with  the  development  of  appendages  on  the  faces.  In  some  cases  this  is  almost 
a  physical  necessity,  since  the  bracts  are  so  compactly  placed  in  the  glomerules  that  any 
considerable  outgrowth  of  appendages  necessitates  an  elongation  of  the  base  in  order  to 
provide  the  space  necessary  for  their  development.  If  the  appendage  character  is  to  be 
used  specifically,  it  should  be  so  employed  throughout  the  group  at  least.  The  futility 
of  such  a  course  is  demonstrated  by  a  scrutiny  of  herbarium  specimens,  fully  50  per  cent 
of  which  exhibit  both  smooth  and  appendaged  bracts  on  single  stems  (plate  44,  figs. 
10  to   15). 

Similar  difficulties  are  encountered  in  an  attempt  to  use  the  dentation  of  the  leaves. 
Throughout  the  whole  species,  but  especially  in  expansa,  there  is  a  general  tendency  of 
the  leaves  to  be  repand  or  sinuate-dentate.  This  shows  even  in  dried  specimens,  through 
the  unequal  folding  of  the  margins.  Finally,  the  distribution  of  the  staminate  flowers  is 
found  to  be  far  from  constant.  They  are  usually  wanting  in  mature  pistillate  clusters, 
but  this  is  often  because  they  have  matured  ahead  of  the  fruits  and  been  crowded  off. 
They  sometimes  form  pure  terminal  spikes,  although  this  can  not  be  correlated  with 
other  characters.  The  most  notable  examples  of  elongated  staminate  spikes  or  panicles 
are  found  in  a  collection  of  expansa  (Westminster,  Orange  County,  California,  June  20, 
1896,  McClatchie  (UC)  and  in  A.  rydbergi  (minor  variation  9).  The  distribution  of  the 
staminate  clusters  is  perhaps  correlated  with  nutrition  factors,  and,  if  so,  it  can  have  no 
phylogenetic  value.  Since  the  characters  just  mentioned  are  thus  found  to  be  entirely 
unreliable,  the  only  course  open  is  to  refer  all  species  based  upon  them  to  the  category  of 

minor  variations. 

ECOLOGY. 

Atriplex  argentea  is  one  of  the  most  widely  distributed  annuals  of  its  genus,  occurring 
as  a  pioneer  family  or  consocies  in  moderately  alkaline  areas  throughout  the  West.  While 
the  two  subspecies  are  complementary  in  distribution,  they  exhibit  essentially  the  same 
ecologic  behavior.  Determinations  of  the  salt-content  by  Kearney  and  his  associates 
have  given  0.27  per  cent  in  the  first  foot,  and  0.2  for  the  second.  It  grows  frequently 
with  Salsola,  Suaeda,  or  Distichlis,  as  well  as  with  other  species  of  Atriplex.  Both  forms 
often  leave  their  alkaline  habitat  to  become  weeds  in  fallow  fields  and  disturbed  places, 
usually  constituting  the  initial  stage  of  a  short  subsere.  The  plants  bloom  chiefly  in 
June  and  July,  but  they  begin  in  May  and  sometimes  last  as  late  as  October  in  moist 
fields.     The  subspecies  expansa  is  an  important  host-plant  of  Eutettix  tenella  (p.  308). 


288  GENUS   ATRIPLEX. 


There  is  probably  no  commercial  value  to  this  saltbush,  notwithstanding  reports  from 
Colorado  that  it  is  frequently  fed  as  hay,  and  others  from  southern  California  that 
expansa  makes  good  hay  if  cut  in  May  and  treated  like  wheat  or  barley  hay  (Calif.  Agr. 
Exp.  Sta.  Rep.  1898-1901,  367).  The  difficulty  of  utilizing  the  wild  growth  is  that  it 
seldom  forms  solid  stands,  but  usually  grows  sparsely  on  disturbed  soils,  especially  in 
stubble.  If  it  is  really  palatable  to  stock,  as  indicated  in  the  reports  referred  to,  it  might 
be  profitably  used  as  a  summer  crop  to  follow  hay  on  moderately  alkaline  soils,  thus  serv- 
ing at  once  to  supply  food  for  stock  and  to  remove  the  alkali.  It  is  possible,  too,  that  it 
might  be  used  for  ensilage.  Detailed  chemical  studies  and  feeding  experiments  have 
been  reported  upon  by  Headden  (Colo.  Agr.  Exp.  Sta.  Bull.  14:61-76,  1907) ;  a  description 
and  chemical  analysis  are  given  by  Knight,  Hepner,  and  Nelson  (Wyo.  Agr.  Exp.  Sta. 
Bull.  65:48,  1905) ;  and  information  on  germination  and  growth  under  cultural  conditions 
are  supplied  by  Elias  Nelson  (Wyo.  Agr.  Exp.  Sta.  Bull.  63:1-19,  1904).  The  general 
experience  of  stock-feeders  is  that  Atriplex  furnishes  only  an  inferior  feed  which  animals 
will  not  eat,  except  in  times  of  great  nee'd. 

Since  the  pollen  is  a  frequent  cause  of  hay-fever,  it  is  used  by  specialists  in  the  prepara-' 
tion  of  extracts  for  the  prevention  of  this  disease.  The  methods  employed  have  been 
described  under  Atriplex  rosea  (p.  260). 

22.  ATRIPLEX  CORONATA  Watson,  Proc.  Am.  Acad.  9: 114, 1874.    Plate  43.   Crownscale. 

Erect  or  spreading  annual  herb,  1  to  3  dm.  high,  branched  from  the  base  and  bushy  or 
sometimes  simple  below;  branches  stout  or  slender,  not  angled,  furfuraceoUs,  glabrate  in 
age,  the  bark  then  stramineous;  leaves  alternate  except  the  lower,  all  but  the  upper  ones 
petiolate,  mostly  approaching  elliptic,  but  nearly  all  broadest  below  the  middle,  the  upper 
ones  ovate  (never  deltoid  nor  with  hastate  base),  middle  and  lower  ones  decidedly  nar- 
rowed to  the  base,  all  acute  at  apex,  0.5  to  2.5  cm.  long,  0.3  to  1  cm.  wide,  entire,  thin, 
grayish  furfuraceous,  glabrate;  flowers  monoecious,  in  dense  axillary  glomerules,  the  pis- 
tillate in  nearly  all  of  the  axils,  the  staminate  mixing  with  them  in  the  upper  axils  and 
perhaps  forming  pure  glomerules  near  the  ends  of  the  branches  (naked  staminate  spikes 
not  thus  far  found) ;  perianth  of  4  or  5  sepals  in  the  staminate  flowers,  wanting  in  the  pis- 
tillate; fruiting  bracts  sessile,  compressed,  united  to  above  the  middle,  broadly  obovate 
or  flabelliform,  3  to  4  or  rarely  5  mm.  long,  3  to  5.5  mm.  broad,  mostly  broader  than  long, 
the  green  foliaceous  margins  irregularly  dentate  or  laciniate,  the  faces  smooth  (except  for 
the  dense  scurf)  to  cristate  with  numerous  long  appendages;  seed  1  to  1.5  mm.  long,  dark 
purplish-brown  or  burnt  umber,  shining;  radicle  superior. 

Interior  of  California,  from  the  lower  Sacramento  Valley  throughout  the  San  Joaquin 
Valley,  where  common,  to  San  Jacinto  Lake,  Riverside  County,  and  perhaps  to  Lower 
California.  Type  locality  given  as  San  Joaquin  Valley,  California,  in  alkaline  soil 
{Brewer  1189),  and  near  Fort  Mojave  {Cooper);  but  Brewer  states  in  his  Field  Book  that 
No.  1189  came  from  an  alkaline  valley  in  Livermore  Pass.  This  pass  is  on  the  westerly 
side  of  the  San  Joaquin  Valley  and  just  southeast  of  Mount  Diablo.  The  Fort  Mojave 
reference  is  probably  an  error.  Collections  (all  from  California):  Collinsville,  Solano 
County,  May  13,  1892,  Jepson  (Herb.  Jepson,  type  of  A.  verna  Jepson,  minor  variation 
5);  4  km.  north  of  Collinsville,  Hall  11015  (UC,  same  variation);  between  Antioch  and 
Marsh  Creek,  Contra  Costa  County,  May  3,  1907,  Brandegee  (UC);  type  collection, 
Brewer  1189  (Or,  UC,  US) ;  near  Chowchilla,  Madera  County,  Hall  11758  (UC) ;  Santa  Fe 
Canal,  near  Los  Banos,  Merced  County,  July  9,  1921,  Kennedy  (UC);  near  Dos  Palos, 
Merced  County,  Hall  11020  (UC);  near  Kern  Lake,  Davy  2135,  2138  (UC,  minor  varia- 
tion 5,  A.  verna  Jepson);  dried  Jaed  of  San  Jacinto  Lake,  May  17,  1901,  Jepson  1240 


A.    CORONATA.  289 

(Herb.  Jepson,  type  of  A.  coronata  notatior,  Jepson,  minor  variation  1);  same  collection, 
Hall  1800  (US,  same  variation);  San  Jacinto  Valley,  Vasey  549  (Gr,  US,  type  collection 
of  A.  sordida  Standley,  minor  variation  4). 

MINORiVARIATIONS  AND  SYNONYMS. 

1.  Atriplex  coronata  var.  notatior  Jepson,  Fl.  Calif.  437,  1914.— Sides  of  the  bracts  copiously  toothed- 
crested,  the  fruits  thus  globose  in  outline,  otherwise  as  in  the  typical  form.  Described  from  specimens  gathered 
at  San  Jacinto  Lake,  California.  These  bracts  exhibit  the  extreme  development  of  appendages,  but  they 
are  approached  by  bracts  of  other  collections  in  which  almost  all  degrees  of  intergradation  occur  (e.  g.,  Hall 
11020,  UC).    The  variability  of  this  feature  in  the  closely  related  A.  argentea  is  illustrated  in  plate  44. 

2.  A.  coronata  var.  verna  Jepson,  Fl.  W.  Middle  Calif.  179,  1901. — Based  on  A.  verna,  which  see. 

3.  A.  ELEGANs  var.  coronata  Jones,  Contr.  West.  Bot.  12 :76,  1908. — Although  coronata  and  elegam  belong 
to  the  same  major  group,  there  is  no  apparent  reason  for  assuming  that  they  are  any  closer  to  each  other  than 
either  one  is  to  any  of  several  other  species.  The  bracts  are  much  less  strongly  compressed  and  never  approach 
the  evenness  of  dentation  so  characteristic  of  elegans.  The  suggestion  that  the  plants  may  sometimes  be 
biennial  does  not  receive  support  from  extensive  field  observations. 

4.  A.  sordida  Standley,  N.  Am.  Fl.  21 :47,  1916. — This  is  a  very  doubtful  form  because  of  the  incomplete 
nature  of  the  type,  the  middle  and  lower  leaves  being  unknown.  Possibly  it  is  a  variant  from  A.  cordulata 
with  exceptionally  blunt  bracts,  but  since  these  are  broadest  above  the  middle  and  there  is  a  tendency  in  some 
of  the  lowest  leaves  present  to  be  narrowed  to  the  base,  it  is  probably  to  be  referred  to  coronata.  The  type 
is  a  piece  from  apparently  a  large  bushy  plant  with  many  close  ascending  branches;  the  sides  of  the  bracts 
smooth  or  with  only  a  few  small  protuberances;  the  herbage  loosely  white-furfuraceous,  as  is  common  in  coronata 
and  cordulata.  The  type  locality  is  San  Jacinto  Valley,  Riverside  County,  California  (Vasey  649,  US).  The 
distribution  is  given  as  Riverside  and  Los  Angeles  Counties,  but  no  specimens  from  the  latter  can  now  be 
found  in  the  herbaria. 

5.  A.  VERNA  Jepson,  Pittonia  2:305,  1892. — A  low,  closely  branched  form  with  its  type  locality  at  CoUins- 
ville,  Solano  County,  California.  More  recent  collections  around  CoUinsville  include  plants  from  4  to  20  cm. 
high.  Similar  reduced  forms  come  from  as  far  south  as  the  Upper  San  Joaquin  Valley.  Plants  only  8  to  12 
cm.  high,  but  very  stout  and  with  numerous  short,  stout  branches  have  been  collected  on  Marsh  Creek,  east 
of  Mount  Diablo  (May,  1883,  Brandegee,  UC).  All  of  these  characters  appear  to  represent  only  ecologic  re- 
sponses, although  a  similarly  reduced  form  of  the  closely  related  A.  argentea  seems  to  be  confined  to  a  par- 
ticular geographic  area  (A.  argentea  hillmani,  minor  variation  1  under  argentea).  Seasonal  conditions  seem 
to  be  responsible  for  the  verna  form  only  in  part,  since  plants  have  been  gathered  as  late  as  midsummer.  The 
reduction  of  verna  to  coronata  was  first  made  by  its  author  (Jepson,  Fl.  Calif.  437,  1914). 

RELATIONSHIPS. 

The  natural  position  of  this  species  is  somewhere  near  A.  argentea  and  A.  cordulata, 
with  both  of  which  it  has  been  confused  at  times.  It  differs  from  both  in  the  more  nearly 
eUiptic  leaves,  most  of  which  are  much  narrowed  at  base.  As  compared  with  argentea, 
the  fruiting  bracts  are  almost  always  smaller,  although  a  few  of  the  largest  are  larger 
than  the  smallest  found  on  that  species.  The  leaves,  too,  are  much  more  reduced,  except 
that  in  a  minor  variation  under  argentea  (No.  1,  hillmani)  they  are  about  as  in  coronata. 
If  these  two  species  are  connected  phylogenetically,  the  connection  is  probably  through 
this  reduced  form  of  argentea  rather  than  through  its  subspecies  expansa,  notwithstanding 
the  overlapping  geographic  ranges  of  the  latter  and  A.  coronata. 

The  relationship  with  A.  cordulata  is  less  direct,  although  the  morphologic  differences 
are  of  such  a  nature  that  it  is  sometimes  almost  impossible  to  identify  herbarium  speci- 
mens as  the  one  or  the  other.  This  is  partly  because  the  upper  leaves  are  practically  the 
same,  being  more  or  less  ovate  and  subcordate  in  both,  while  the  lower  leaves  are  usually 
wanting  at  fruiting  time,  when  most  of  the  collections  are  made.  The  decidedly  nar- 
rowed or  rounded  bases  of  the  middle  and  lower  leaves  of  coronata  are  very  distinctive, 
when  present.  The  upper  leaves  are  more  narrowly  ovate  than  in  cordulata  and  with  less 
pronouncedly  cordate  bases.  The  fruiting  bracts,  too,  are  distinctive  when  carefully 
compared  and  when  allowance  is  made  for  deception  due  to  unequal  development  of  the 
margins  and  appendages.  In  coronata  the  mature  normal  bracts  are  of  the  obovate 
type  and  are  broadest  at  or  above  the  middle;  in  cordulata  they  are  of  the  ovate  type 


290  GENUS  ATKIPLEX. 

with  a  broad  base  and  widest  below  the  middle  (exclusive  of  the  stalk  when  this  is  pres- 
ent). The  bracts  in  both  are  slightly  broader  than  long.  Dififerences  in  habit  are  of 
assistance  at  times.  A.  coronata,  as  far  as  known,  never  assumes  the  rigid,  erect  habit 
of  cordulata,  but  this  latter  also  has  branched  and  spreading  forms. 

The  type  specimens  of  A.  coronata  are  unsatisfactory  in  that  they  are  both  immature 
and  incomplete.  At  this  stage  they  display  very  clearly  the  subelliptic  shape  of  the 
leaves,  with  the  bases  much  narrowed.  Some  of  the  bracts  are  smooth  on  the  sides,  and 
some  have  low  crests.  The  herbage  is  well  developed  and  perhaps  somewhat  flaccid  as 
compared  with  recent  collections,  but  these  latter  are  all  from  much  overgrazed  areas 
where  they  have  suffered  from  trampling  and  hard  soil  as  well  as  from  grazing. 

ECOLOGY  AND  USES. 

Atriplex  coronata  behaves  much  like  argentea,  though  it  grows  as  a  halophyte  in  more 
alkaline  places,  and  it  is  not  so  strongly  ruderal.  In  the  original  habitat  it  forms  a  pioneer 
consocies  in  soil  containing  2  per  cent  or  more  of  salt,  even  being  found  in  the  Spiro- 
stachys  zone.     The  plants  bloom  from  May  to  July. 

This  species  is  one  of  the  important  host-plants  of  Eutettix.  It  is  grazed  to  some  extent 
by  cattle  and  sheep  in  the  San  Joaquin  Valley  of  California. 

23.  ATRIPLEX  POWELLI  Watson,  Proc.  Am.  Acad.  9:114.  1874.     Plate  45.     Ribscale. 

Strictly  erect  annual  herb,  1  to  10  dm.  high,  sparingly  branched  from  the  base  to  form 
an  open  pyramidal  or  columnar  plant;  branches  ascending  or  erect,  slender  or  moderately 
stout,  somewhat  woody  and  brittle  in  age,  obtusely  angled,  whitish  furfuraceous,  gla- 
brate,  the  old  bark  exfoliating  in  dull  white  patches;  leaves  all  or  mostly  alternate,  the 
lower  on  petioles  often  as  long  as  the  blades,  the  upper  sessile,  broadly  ovate  or  rhombic- 
ovate,  rounded  or  abruptly  cuneate  at  base,  acute  at  apex,  1  to  3.5  cm.  long  exclusive  of 
petiole,  0.8  to  3  cm.  wide,  entire,  firm,  not  fleshy,  gray  especially  beneath  with  a  fine 
scurf,  prominently  3-nerved  from  the  base;  flowers  imperfectly  dioecious,  some  plants 
purely  pistillate,  some  chiefly  staminate,  but  with  a  few  pistillate  flowers  in  the  lower 
axils,  others  chiefly  pistillate  below  and  staminate  above,  the  flowers  all  in  axillary  glom- 
erules  which  are  exceeded  by  their  subtending  leaves;  perianth  of  staminate  flowers  4-  or 
5-cleft,  wanting  in  the  pistillate  flowers;  fruiting  bracts  sessile,  thick,  united  to  the  sum- 
mit, broadly  spatulate  or  broadly  oblong,  ending  above  in  a  broad  flattened  usually 
truncate  green  terminal  lobe,  3  to  4  mm.  long  and  broad,  the  faces  covered  with  promi- 
nent thickened  ascending  processes,  or  these  sometimes  nearly  wanting;  seed  2  mm.  long, 
greenish-yellow;   radicle   superior. 

Alkaline  plains  from  Alberta  to  eastern  Colorado,  New  Mexico,  Arizona,  and  Utah. 
Type  locality,  Arizona.  Collections:  Rosedale,  Alberta,  Moodie  4  (US);  vicinity  of 
Rosedale,  Alberta,  Moodie  1182  (DS,  NY);  near  Glendive,  Montana,  1883  Ward  (US); 
Shelby,  Montana,  September  11,  1909,  Jones  (Herb.  Jones);  Carson  County,  South 
Dakota,  Over  3425  (US) ;  Wamsutter,  Wyoming,  Nelson  3673  (R,  UC,  US) ;  Howell  Lake, 
Wyoming,  Nelson  5311  (Herb.  Jones,  type  of  A.  nelsoni  Jones,  minor  variation  1) ;  Lara- 
mie River,  Huttons  Grove,  Albany  County,  Wyoming,  Nelson  8171  (Gr,  NY,  R,  US, 
type  collection  of  A.  philonitra  Nelson,  minor  variation  2);  Colorado:  Montrose,  »S/iear 
4929  (NY,  US) ;  Hotchkiss,  Cowen  2185  (Gr,  NY,  R,  US) ;  east  of  Canon  City,  Hall  11082 
(UC);  Mancos  Plains,  Brandegee  1277  (UC);  Gunnison  River,  Purpus  212  (UC);  Grand 
Junction,  Baker  930  (UC,  US);  near  Dulce,  New  Mexico,  Standley  8149  (US);  south  of 
Shiprock,  northwestern  New  Mexico,  Hall  11 146  (UC);  type  collection,  cultivated  from 
Arizona  seed  (Gr) ;  Holbrook,  Arizona,  Rusby  796  (US) ;  4  km.  south  of  Adamana,  Arizona, 
Hall  11161  (CI) ;  near  Green  River,  Utah,  Hall  11037, 11039  (UC) ;  5  km.  north  of  Emery, 
Utah,  Jones  5466  (UC).     Other  localities  represented  by  collections  in  the  M.  E.  Jones 


A.    POWELLI. 


291 


Herbarium,  Salt  Lake  City,  include  Marysvale,  Sunnyside,  and  Cainville,  all  in  Utah. 
Additional  Wyoming  localities  represented  at  the  Rocky  Mountain  Herbarium  are 
Point  of  Rocks,  Middle  Fork  of  Powder  River,  and  Claremont,  Johnson  County. 

MINOR  VARIATIONS. 

1.  Atriplex  nelsoni  Jones,  Contr.  West.  Bot.  11:21,  1903.— Described  from  plants  in  which  the  fruiting 
bracts  are  mostly  smooth  on  the  sides,  the  margins  bearing  a  few  large  herbaceous  lobes.  The  shape  of  the 
terminal  lobe,  the  venation  of  the  leaf,  and  other  characters  positively  assign  this  to  powelli,  which  species 
apparently  was  overlooked  or  misunderstood  when  the  description  of  nelsoni  was  prepared. 

2.  A.  PHiLONiTRA  Nelson,  Bot.Gaz.  34:358,  1902.— The  description  and  the  types  are  both  as  in  genuine 
powelli.     Type  locality,  Laramie  River,  Wyoming. 

RELATIONSHIPS. 

The  characters  of  this  species  are  so  remarkably  fixed  that  it  can  not  be  connected 
closely  with  any  other.  It  appears  to  be  not  a  modification  of  any  existing  form  but  the 
end  of  a  branch  from  near  the  beginning  of  the  argentea  group.  It  is  not  primitive,  as  is 
indicated  by  the  absence  of  a  perianth  in  the  pistillate  flowers,  the  unusual  development  of 
the  fruiting  bracts,  and  the  attainment  of  partial  dioecism.  In  this  last-named  feature 
it  has  progressed  far  beyond  its  nearest  allies.  In  the  Green  River  district  of  eastern 
Utah  the  differentiation  into  pistillate  and  staminate  individuals  is  so  marked  that  the 
prevailing  sex  may  be  determined  at  a  glance.'  Here  the  pistillate  plants  are  strictly 
erect,  with  more  numerous  and  larger  leaves  than  occur  on  the  staminate.  They  bear 
no  male  flowers.  On  the  other  hand,  the  staminate  plants  bear  a  few  pistillate  bracts 
in  the  lower  axils  of  the  inflorescence.  The  staminate  flowers  open  before  the  pistillate 
on  neighboring  plants.  At  Green  River  Station  some  plants  have  about  as  many 
staminate  as  pistillate  flowers,  a  proportion  also  found  on  herbarium  sheets  from  other 
localities.  Along  the  Laramie  River,  Wyoming,  the  axial  branch  of  each  plant  is  usually 
wholly  staminate,  according  to  Nelson  (Bot.  Gaz.  34:358,  1902,  under  A.  ■philonitra) . 
The  type  material  at  the  Gray  Herbarium  consists  of  3  plants,  2  purely  pistillate,  the 
third  about  half  pistillate  and  half  staminate.  None  of  these  are  very  leafy.  Thus  it 
seems  that  this  species  is  in  a  progressive  stage  of  evolution  and  that  it  is  headed  toward 
a  complete  dioecism  like  that  obtaining  in  the  shrubby  species  of  Atriplex.  The  shape 
and  venation  of  the  leaves  supply  evidence  that  it  is  perhaps  as  close  to  A.  argentea  as 
to  any  other  species. 

Some  taxonomic  confusion  has  come  about  through  a  misunderstanding  of  A.  powelli. 
Perhaps  this  resulted  from  the  inadequate  descriptions  of  the  peculiar  fruiting  bracts. 
For  some  time  collections  were  labeled  as  a  form  of  A.  expansa,  with  which  it  can  not 
possibly  be  confused  when  attention  is  given  to  the  bract  characters  or  even  to  the  vena- 
tion of  the  leaf.  This  led  Nelson  to  redescribe  it  as  A.  philonitra,  and  Jones,  who  had  a 
slightly  different  form,  as  A.  nelsoni.  These  names  were  reduced  into  synonymy  by 
Standley  (N.  Am.  Fl.  21:48,  1916),  who,  having  access  to  the  type  specimens  of  powelli, 
noted  the  practical  identity  of  all  three. 

ECOLOGY  AND  USES. 

Atriplex  powelli  is  a  characteristic  indicator  of  abundant  surface  alkali,  usually  occur- 
ring in  pure  stands  in  alkaUne  valleys  and  plains.  It  regularly  forms  the  initial  consocies 
in  such  areas  throughout  most  of  southern  Wyoming,  Colorado,  Utah,  and  northern  New 
Mexico  and  Arizona.  The  perennial  zone  around  is  occupied  by  A.  nuttalli  and  corrugata, 
by  the  first  alone,  or  with  Sarcobatus  or  Sporobolus  airoides.  While  it  may  grow  in 
depressions  along  roadsides,  it  rarely  becomes  a  true  ruderal,  probably  owing  to  the  com- 
petition of  more  successful  halophytes,  such  as  Salsola.  The  plants  flower  from  July 
through  October. 

Watson  states  that  the  fruits  are  collected  by  the  Indians  for  food  (Proc.  Am.  Acad. 
9:115,1874). 


292  GENUS   ATRIPLEX. 

24.  ATRIPLEX  LEUCOPHYLLA(Moquin)  Dietrich,  Syn.  PI.  5: 536, 1852.    Plate  45.    Seascale. 

Prostrate  perennial  herb  with  ascending  or  erect  leafy  shoots  from  an  often  somewhat 
woody  base,  the  above-ground  portions  1  to  3  dm.  high,  sometimes  forming  open  mats 
3  to  10  dm.  across;  branches  stout,  obtusely  angled  when  old,  often  pinkish,  coarsely 
white-mealy,  tardily  glabrate  and  the  bark  then  yellowish  white ;  leaves  alternate  or  those 
at  the  base  of  each  shoot  opposite,  crowded,  sometimes  loosely  imbricated,  sessile,  orbic- 
ular-ovate or  broadly  elliptic  or  rarely  obovate,  narrowed  or  rounded  to  the  base,  obtuse 
at  apex,  1  to  3.5  cm.  long,  0.5  to  1.5  cm.  wide,  entire,  very  thick,  densely  coated  with  a 
permanent  brownish  or  gray  scurf,  1-  or  3-nerved,  sometimes  even  the  midnerve  obscure; 
flowers  monoecious,  the  staminate  glomerules  in  dense  stout  terminal  mostly  simple 
spikes,  the  pistillate  flowers  few  at  a  place  in  the  upper  axils;  perianth  5-cleft  in  the 
staminate  flowers,  wanting  in  the  pistillate;  fruiting  bracts  sessile,  spongious,  not  com- 
pressed, completely  united  except  at  apex,  elliptic-globose,  acutish,  5  to  7  mm.  long,  4 
to  5  mm.  broad,  entire  or  dentate,  the  faces  at  least  lumpy  and  commonly  with  two  or 
several  wart-hke  projections,  not  nerved;  seed  2.5  to  3  mm.  long,  very  dark  reddish 
brown;  radicle  superior.  {Obione  leucophylla  Moquin,  in  DeCandolle,  Prodr.  13=':109, 
1849.) 

Sea-beaches  of  California  and  Lower  California  and  the  adjacent  islands,  from  Hum- 
boldt Bay  to  Viscaino  Bay;  casual  inland  at  Lake  Elsinore.  Type  locaUty,  Cahfornia. 
Collections,  all  in  California  and  Lower  California:  Sand  hills  of  ocean  beach  at  Samoa, 
opposite  Eureka,  Tracy  1264  (UC,  see  minor  variations) ;  Bucksport,  Humboldt  Bay, 
Tracy  Ui6  (UC,  same  variation);  Point  Reyes,  Marin  County,  Davy  6763  (UC);  West 
Berkeley,  December,  1896,  Davy  (UC);  Alameda  Marshes,  September  24,  1898,  Davy 
(UC);  Point  Lobos,  San  Francisco,  August  20,  1891,  Jepson  (Gr,  NY,  UC,  US);  Tobin, 
San  Mateo  County,  August  11,  1913,  Brandegee  (UC);  Monterey,  Heller  6858  (UC); 
Pacific  Grove,  Elmer  4109  (UC);  San  Simeon,  San  Luis  Obispo  County,  July,  1887, 
Brandegee  (UC) ;  San  Miguel  and  Santa  Cruz  Islands  (according  to  Brandegee,  Zoe  1 :  145, 
1890);  Ventura  Beach,  October  19,  1919,  Hall  (CI);  Avalon,  Santa  Catahna  Island,  at 
one  locality  only,  April,  1896,  Trask  (US,  see  minor  variations);  San  Nicholas  Island, 
April,  1901,  Trask  (Gr);  San  Clemente  Island,  Nevin  and  Lyon  29  (Gr);  Santa  Monica, 
Davy  2733  (UC);  Redondo,  October  15,  1893,  Brandegee  (UC);  Lake  Elsinore,  J.  D. 
Abrams  (DS);  La  Jolla,  San  Diego  County,  Clements  57  (Gr,  NY,  UC);  South  San  Diego, 
Chandler  4009  (UC);  Enseiiada,  August  27,  1893,  Brandegee  (UC);  Todos  Santos,  June 
2,  1883,  Fish  (US);  Lagoon  Head,  Palmer  812  (Gr,  NY,  UC);  Coast  near  Ascension 
Island,  April  17,  1897,  Brandegee  (UC). 

MINOR  VARIATIONS. 

This  is  one  of  the  least  variable  of  all  the  North  American  species.  Such  variations  as  occur  are  due  chiefly 
to  differences  in  size  and  habit  and  in  the  appendages  of  the  bracts.  Mrs.  Trask  has  noted  an  exceptionally 
small-leaved  form  at  Avalon,  Santa  Catalina  Island.  In  this  the  leaves  are  only  1.2  by  0.5  cm.  in  size.  It  is 
doubtless  the  result  of  unfavorable  soil  conditions  or  perhaps  of  inbreeding,  for  the  species  is  very  rare  on  this 
island.  A  specimen  with  scarcely  larger  leaves  comes  from  South  San  Diego  {Chandler  4009,  UC),  while  in  two 
collections  from  Humboldt  Bay  (Tracy  1264  and  4416,  UC),  at  the  northern  limit  of  the  range  of  the  species, 
the  leaves  are  even  smaller  than  in  the  Santa  Catalina  Island  plant. 

RELATIONSHIPS. 

No  direct  connection  can  be  traced  between  this  species  and  any  other.  It  certainly 
belongs,  however,  to  the  group  best  represented  by  A.  pentandra,  A.  coulteri,  etc.  Each 
of  these  is  more  highly  specialized  than  leucophylla  in  certain  particulars,  and  all  of  the 
group  have  much  more  reduced  and  otherwise  modified  seeds  and  fruiting  bracts.  It 
seems  probable,  therefore,  that  leiicophylla  had  its  origin  in  Mexico  and  that  it  became 


A.  LEUCOPHYLLA- 


PENTANDRA. 


293 


separated  from  the  ancestral  line  during  its  northward  migration.  A  close  study  of  forms 
in  Lower  California  and  on  the  mainland  of  western  Mexico  may  bring  further  evidence 
to  bear  on  this  question. 

ECOLOGY  AND  USES. 

Atriplex  leucophylla  may  constitute  the  pioneer  consocies  on  the  strand  just  beyond  the 
reach  of  the  waves,  or  it  may  form  dunelets  in  moving  sand  farther  back.  It  grows  alone 
over  much  of  its  zone,  but  behind  it  is  associated  with  Abronia  maritima,  A.  umbellata, 
Franseria  bipinnatifida,  Mesembryantheum  nodiflorum,  or  Distichlis.  The  prostrate 
woody  stems  and  the  numerous  erect  branches  enable  it  to  resist  erosion,  and  to  accumu- 
late wind-blown  sand  in  small  amounts.  It  is  a  marked  halophyte,  as  indicated  by  its 
habitat,  and  the  dense  scurf  of  leaves  and  stems.  The  flowers  appear  from  April  to 
October. 

No  uses  are  known  for  this  plant,  though  it  is  doubtless  an  occasional  cause  of  hay- 
fever. 


Perennials  ;lvs.  entire,  reduced 
(0.5-2  cm.  long,  under  0.5  cm.  wide); 
'      (Californian) 


Phylogenetic  chart  of  the  Atriplex  pentandra  group. 


294  GENUS   ATRIPLEX. 

25.  ATRIPLEX  PENTANDRA  (Jacquin)  Standley,  N.  Am.  Fl.  21:54,  1916.     Plate  46. 

Decumbent  or  sometimes  erect  annual  or  perennial  herb  or  the  base  suffrutescent,  1 
to  8  dm.  high,  branched  throughout  to  form  a  spreading  bushy  plant  often  of  irregular 
outline;  branches  obtusely  angled  or  nearly  terete,  not  striate,  sparsely  scurfy  but  early 
glabrate  and  then  stramineous,  the  pale  bark  persistent  but  breaking  longitudinally  on 
old  stems;  leaves  all  alternate,  except  probably  the  lower,  with  very  short  petioles  or  the 
upper  ones  sessile,  elliptic  to  spatulate  or  obovate,  rarely  lanceolate,  tapering  or  rounded 
at  the  base,  obtuse  or  acute  at  apex,  commonly  mucronate,  0.5  to  4  cm.  long,  0.2  to  15. 
cm.  wide,  entire  or  sinuate  or  acutely  dentate,  thin,  sparsely  scurfy  and  greenish  on  the 
upper  surface,  densely  white-scurfy  beneath,  or  white  on  both  surfaces  in  some  island 
forms  (subspecies  confinis),  1-nerved;  flowers  monoecious,  the  staminate  glomerules 
either  solitary  or  in  terminal  spikes  up  to  3  cm.  (or  more?)  long,  the  pistillate  flowers  in 
small  axillary  glomerules  and  sometimes  mixing  with' the  lower  staminate;  perianth 
5-cleft  in  the  staminate  flowers,  wanting  in  the  pistillate ;  fruiting  bracts  sessile  or  short- 
stalked,  compressed,  united  to  about  the  middle,  obovate  or  orbicular-obovate,  com- 
monly with  broad  thin  margins,  2.5  to  6  mm.  long,  3  to  6  mm.  broad,  sharply  and  saliently 
dentate  above  the  middle,  the  faces  variously  crested  or  tubercled  or  smooth,  often  reticu- 
late-veined; seed  0.8  to  1.5  mm.  long,  brown;  radicle  superior.  {Axyris  pentandra  Jacquin, 
Sel.  Stirp.  Am.  244,  1763.) 

Mexico  and  States  bordering  the  Gulf  of  Mexico  to  the  West  Indies  and  along  the 
Atlantic  Coast  to  New  Hampshire,  also  in  South  America. 

SUBSPECIES. 
Artificial  Key  to  the  Subspecies  of  Atriplex  pentandra. 
Leaves  sparsely  scurfy  and  greenish  on  the  upper  surface;  fruiting  bracts  mostly  crested  or 
tubercled. 
Bracts  3  to  6  mm.  long.     Eastern. 

Leaves  broadly  elhptic  to  obovate;  bracts  4  to  6  mm.  long.     Virginia  to  New  England,  (a)  arejiaria  (p.  294). 
Leaves  elliptic  to  lanceolate  or  linear;  bracts  3  to  4  mm.  long  (rarely  4.5  mm.). 

Eastern  Mexico  to  West  Indies  and  the  South  Atlantic  States (6)  lypica  (p.  294). 

Bracts  2.5  to  3  mm.  long  (rarely  3.5  mm.).     Western (d)  muricaia  (p.  296). 

Leaves  densely  and  permanently  white-scurfy  on  both  sides;  fruiting  bracts  (about  3  mm. 

long)  not  crested  or  tubercled.     West  Indies (c)   confinis  (p.  295). 

25a.  Atriplex  pentandra  arenaria  (Nuttall). — Stem  erect  from  an  annual  taproot, 
or  the  lateral  branches  procumbent;  leaves  elliptic  to  broadly  oblong  or  obovate,  tapering 
to  the  base,  obtuse  or  the  upper  acute  at  summit,  1.5  to  4  cm.  long,  0.5  to  1.5  cm.  wide, 
typically  entire  or  undulate,  but  often  saUently  dentate,  at  first  gray  or  whitish-scurfy 
on  both  sides,  but  soon  greenish  above;  staminate  spikes  3  cm.  or  less  long;  fruiting  bracts 
4  to  6  mm.  long,  4  to  7  mm.  broad,  the  sides  with  2  dentate  crests  or  tuberculate  or  rarely 
smooth,  reticulate-veiny  or  the  veins  covered  by  the  tubercles;  seed  about  1.5  mm.  long. 
{A.  arenaria  Nuttall,  Genera  1 :  198,  1818.)  Sandy  shores  along  the  Atlantic  Coast  from 
New  Hampshire  to  Virginia  and  perhaps  farther  southward.  Type  locality,  sandy  sea- 
coast  of  New  Jersey.  Collections:  Hampton,  New  Hampshire,  Robinson  738  (Gr); 
Katama  Bay,  Marthas  Vineyard,  Massachusetts,  Fernald  75  (Gr,  NY,  UC,  US) ;  Groton, 
Connecticut,  September  9,  1903,  Bissell  (Gr);  Atlantic  City,  New  Jersey,  Martindale  53 
(US);  type,  Nuttall  (Phila);  Gardiners  Island,  Long  Island,  August  15,  1878,  Miller 
(US);  Piney  Point,  Maryland,  1874,  Vasey  (US);  Franklin  County,  Virginia,  Brown 
(Phila). 

256.  Atriplex  pentandra  typica. — Stems  spreading  or  rechning,  but  usually  with 
ascending  or  erect  ends,  from  an  annual  or  perennial  root,  often  suffrutescent  at  base; 
leaves  elliptic  to  narrowly  oblong  or  lanceolate,  acute  at  each  end  or  obtuse  and  mucro- 
nate at  summit,  1  to  3  cm.  long,  0.3  to  1  cm.  wide  (short  and  broad  in  minor  variation 


A.    PENTANDRA. 


295 


13),  entire  to  saliently  and  sharply  dentate,  greenish  above,  gray-scurfy  beneath  (gray 
on  both  sides  in  minor  variation  13) ;  staminate  spikes  either  short,  as  in  the  type,  or  up 
to  2  cm.  long;  fruiting  bracts  3  to  4  or  rarely  4.5  mm.  long,  usually  4  to  5  mm.  broad,  each 
of  the  sides  with  2  dentate  crests  or  tubercled  or  rarely  smooth,  reticulate-veiny  or  the 
veins  covered  by  the  tubercles;  seed  1.2  to  1.5  mm.  long.  (A.  pentandra  Jacquin,  Sel. 
Stirp.  Am.  244,  1763.)  Coast  of  the  South  Atlantic  and  Gulf  States  and  West  Indies; 
also  in  northern  South  America.  Type  locahty,  seashores  of  Cuba.  Collections: 
Indian  River,  Florida,  Curtiss  2357  (Gr,  NY,  US);  shore  of  Upper  Matecumbe  Key, 
Florida,  Curtiss  5506  (NY,  UC,  US) ;  Mon  Louis  Island,  near  Mobile,  Alabama,  August 
15, 1879,  Mohr  (US) ;  Horn  Island,  Mississippi,  Tracy 
6S95(NY,  US) ;  Breton  Island,  Louisiana,  Tracy  and 
Lloyd  42  (Gr,  US);  near  Corpus  Christi,  Texas, 
Heller  1819  (Gr,  US) ;  Atwood  Cay,  Bahamas,  Wilson 
7422  (NY,  form  approaching  subspecies  confinis); 
Grand  Turk  Island,  Bahamas,  Millspaugh  8998 
(NY,  similar  form);  Mariguana,  Bahamas,  Wilson 
7536  (NY);  Ambergris  Key,  Caicos  Group,  Baha- 
mas, Millspaugh  9276  (NY) ;  west  of  Playa  Mariano, 
Havana,  Cuba,  van  Hermann  902  (NY) ;  Playa  del 
Vedado,  Havana,  Cuba,  Baker  1792  (NY);  near 
mouth  of  Bueyvaca,  Province  of  Matanzas,  Cuba, 
Britton  and  Wilson  53  (NY) ;  Cuba,  Wright  3660  (Gr, 
US,  as  A.  aldamae  Grisebach,  minor  variation  1); 
Cayo  Paredon  Grande,  Camaguey,  Cuba,  Shafer 
2741  (Gr,  US) ;  Pedro  Bluff,  Jamaica,  Harris  9932 
(NY,  minor  variation  13);  Morillos  de  Cabo  Rojo, 
Porto  Rico,  Britton,  Cowell,  and  Brown  4714  (NY) ; 
near  Guani  Cay,  Porto  Rico,  Sintensis  3955  (Gr, 
NY) ;  Pinetree  Bay,  St.  Croix,  Rickesecker  327  (Gr, 
NY,  US,  form  approaching  minor  variation  13); 
near  Willemstad,  Curagao,  Britton  and  Shafer  2926 
(NY,  US,  minor  variation  13) ;  Swan  Islands,  off  the 
coast  of  Honduras,  A^e/son  65  (Gr).  Additional  localities  are  mentioned  under  minor 
variations  16  and  18. 

25c.  Atriplex  pentandra  confinis  (Standley). — Stems  probably  spreading  at  base 
from  an  annual  or  perennial  root,  the  ends  erect  or  ascending;  leaves  broadly  elliptic  or 
approaching  rhombic,  rounded  to  the  base,  obtuse  at  summit,  1.5  to  3  cm.  long,  0.5  to 
1.5  cm.  wide  (much  smaller  in  minor  variation  21,  Obione  crispa  Moquin),  typically  low- 
dentate  to  entire  but  varying  to  acutely  dentate  in  small-leaved  forms,  densely  and 
closely  white-scurfy  on  both  faces;  staminate  spikes  short  (0.5  to  1  cm.  long);  fruiting 
bracts  2.5  to  3.5  mm.  long,  3  to  4  mm.  broad,  the  sides  without  appendages  but  with 
strong  reticulations  faintly  visible  through  the  dense  scurf;  seed  about  1.5  mm.  long.  (^4.. 
confinis  Standley,  N.  Am.  Fl.  21 :54,  1916.)  The  Bahamas  to  northern  Venezuela.  Type 
locality.  Sombrero  Island.  Collections:  Type  collection,  1864,  Julien  (NY,  US) ;  Eastern 
Cay,  Turks  Islands,  Bahamas,  Millspaugh  9369  (NY,  minor  variation  21,  Obione  crispa 
Moquin). 

25d.  Atriplex  pentandra  mtjricata  (Humboldt  and  Bonpland). — Stems  procumbent 
or  ascending  from  an  annual  or  perennial  but  short-lived  root;  leaves  elUptic  to  spatulate 
or  narrowly  obovate,  tapering  to  a  mostly  slender  petiole-Uke  base,  obtuse  and  usually 


Atriplex  pentandra  typica.  Tracing  of  the 
entire  plate  accompanying  the  original  descrip- 
tion (Jacquin,  Sel.  Stirp.  Am.  Pict.  pi.  235;. 


296  GENUS   ATRIPLEX. 

mucronulate  at  summit,  0.5  to  2.5  cm.  long,  0.3  to  1  cm.  wide,  acutely  dentate  to  repand- 
dentate  or  the  upper  ones  entire,  densely  white-scurfy  beneath,  greenish-gray  on  the 
upper  surface ;  staminate  spikes  commonly  shorter  than  the  upper  leaves  and  reduced  to 
1  or  2  glomerules  each  but  varying  up  to  2  cm.  long  and  subpaniculate  (especially  in 
minor  variation  14,  A.  pueblensis  Standley) ;  fruiting  bracts  2.5  to  3  or  rarely  3.5  mm.  long 
(exclusive  of  stipe-like  base  when  this  is  present),  2.5  to  4  mm.  broad,  each  of  the  sides 
with  2  dentate  crests  or  smooth  (especially  in  minor  variation  9,  A.  glomerata  Watson), 
1-  or  3-nerved,  not  obviously  reticulated;  seed  0.8  to  1.2  mm.  long.  (A.  muricata  Hum- 
boldt and  Bonpland  in  Willdenow,  Sp.  PI.  4:959,  1806.)  Apparently  throughout 
Mexico,  except  in  the  extreme  south  and  southeast;  known  from  Pueblo  to  Coahuila  and 
Sonora.  Type  locality,  Mexico.  Collections:  Near  Tehuacan,  Puebla,  Pringle  8577 
(UC,  US,  type  collection  of  A.  pueblensis  Standley,  minor  variation  14);  Mexico  City, 
Pringle  8528  (Or,  NY,  UC,  US);  San  Luis  Potosi,  Schaffner  287  (NY,  US);  near  the  City 
of  Durango,  Palmer  295  (Or) ;  vicinity  of  Saltillo,  Coahuila,  Palmer  290  (Or,  NY,  UC, 
US);  "States  of  Coahuila  and  Nuevo  Leon,"  Palmer  1156  (Gr,  US,  type  collection  of 
A.  glomerata  Watson,  minor  variation  9);  Guaymas,  Sonora,  Palmer  119  (US,  doubtful). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Atriplex  aldamae  Grisebach,  Cat.  PI.  Cub.  282,  1866.— A  form  of  A.  penlandra  typica  in  which  the 
fruiting  bracts  are  exceptionally  large  (4  to  5  mm.  long)  and  without  appendages.  Apparently  only  an  occa- 
sional plant  is  found,  indicating  that  it  may  be  the  result  of  favorable  local  conditions.  The  type  came  from 
western  Cuba  and  the  form  is  not  known  elsewhere. 

2.  A.  ARENARIA  Nuttall,  Gen.  1:198,  1818. — A.  pentandra  arenaria.  This  is  not  the  same  as  A.  armaria 
Woods,  Jour.  Fl.  317,  1850,  which  is  used  in  Europe  for  the  plant  properly  known  as  A.  marilima  Hallier. 

3.  A.  coNFiNis  Standley,  N.  Am.  Fl.  21:54,  1916. — A.  pentandra  confinis. 

4.  A.  CRISPA  Urban,  Symb.  Ant.  8:200,  1920. — Based  upon  Ohione  crispa,  which  see. 

5.  A.  CRIST  ATA  Humboldt  and  Bonpland,  in  Willdenow,  Sp.  PI.  4:959,  1806.— Apparently  identical  with 
the  earlier  Axyris  pentandra  and  therefore  the  same  as  Atriplex  pentandra  typica. 

6.  A.  CRisTATA  var.  arenaria  Kuntze,  Rev.  Gen.  PI.  546,  1891. — A.  pentandra  arenaria. 

7.  A.  CYCLOSTEGIA  Standley,  1.  c,  58,  1916. — Known  from  a  single  immature  specimen  collected  near  Her- 
mosillo,  Sonora  [Malthy  222,  US).  Placed  next  to  A.  elegans  by  Standley,  but  the  foliage  and  bracts  indicate 
that  it  is  close  to  A.  penlandra  muricala  and  perhaps  a  robust  development  of  this.  The  leaves  are  large  for 
the  subspecies,  the  largest  ones  being  3.5  cm.  long  by  1.3  cm.  wide.  The  larger  and  more  nearly  mature  bracts 
are  elliptic  in  shape,  much  longer  than  broad,  and  therefore  not  of  the  elegans  type.  The  largest  one  is  5  mm. 
long  by  3  mm.  broad,  including  the  dentate  margins  and  large  terminal  tooth.  It  is  this  elongated  apex  that 
renders  the  bract,  even  at  this  immature  stage,  exceptionally  large  for  subspecies  muricata.  Whether  these 
marked  vegetative  characters  are  the  result  of  especially  favorable  conditions  under  which  this  particular 
specimen  grew,  or  whether  they  are  characteristic  of  all  plants  of  the  Sonoran  coast,  and  therefore  worthy  of 
taxonomic  recognition,  may  be  left  for  more  extensive  collections  to  determine. 

8.  A.  DOMiNGENsis  Standley,  1.  c,  55,  1916. — The  same  as  Ohione  crispa  Moquin,  which  see  in  this  list. 

9.  A.  GLOMERATA  Watson,  in  Standley,  1.  c,  54,  1916. — A.  penlandra  muricata  but  the  faces  of  the  fruiting 
bracts  not  appendaged.     Type  locality,  Parras,  Coahuila. 

10.  A.  MUCRONATA  Rafinesque,  Am.  Mo.  Mag.  2:176,  1818.— A  name  only  incidentally  mentioned  where 
first  used.  Evidently  intended  to  apply  to  A.  areiiaria  Nuttall  (No.  2  of  this  list),  although  A.  laciniala  Lin- 
naeus is  the  name  referred  to.     A  more  complete  discussion  is  given  by  Blake  (Rhodora  17:84,  1915). 

11.  A.  MURICATA  Humboldt  and  Bonpland,  in  Willdenow,  Sp.  PI.  4:959,  1806.— .4.  pentandra  muricata. 

12.  A.  PARViFOLiA  Humboldt,  Bonpland,  and  Kunth,  Nov.  Gen.  Sp.  2 :  192,  1817.— There  is  nothing  in 
the  original  description  to  indicate  that  this  differs  in  any  essential  feature  from  A.  pentandra  muricata.  Type 
locality,  San  Juan  del  Rio,  south  central  Mexico. 

13.  A.  PENTANDRA  TYPICA. — In  One  West  Indian  variation  the  leaves  are  smaller,  broader  in  proportion  to 
their  length,  and  with  a  more  copious  cinereous  scurf  than  in  the  typical  form.  Common  leaf-measurements 
are:  2.5  by  1.2  cm.,  2  by  0.7  cm.,  1.5  by  0.5  cm.  Although  grayish  in  color,  the  leaves  are  not  so  thick  or 
so  whitish  as  in  subspecies  areymria  and  confinis.  Both  this  and  the  typical  form  are  abundant  on  many  of 
the  West  Indian  Islands,  especially  in  Porto  Rico.  Recent  collectors  look  upon  them  as  only  trivial  and 
fluctuating  variations  and  probably  ecads.     The  following  represent  the  gray,  small-leaved  form:    Cayo 


A.    PENTANDRA.  297 

Muertos,  Porto  Rico,  Britton,  Cornell,  and  Brovm  5036  (NY,  US) ;  Pedro  Bluff,  Jamaica,  Harris  9932  (NY, 
US);  near  Willemstad,  Curasao,  Britton  and  Shajer  2926  (NY,  US). 

14.  A-  PUEBLENSis  Standley,  1.  c,  56,  1916. — The  same  as  A.  pentandra  muricata,  but  a  form  with  unap- 
pendaged  bracts  (as  in  minor  variation  9,  A.  glomerata  Watson)  and  the  staminate  glomerules  in  naked  terminal 
spikes.  The  leaves  are  described  as  entire,  but  this  varies  in  the  type  collection  (although  not  in  the  type 
specimen)  as  pointed  out  by  Macbride  (Contr.  Gray  Herb.  53:10,  1918).  A  duphcate  of  the  type  at  the 
University  of  Cahfornia  has  leaves  mostly  entire,  but  some  with  a  few  minute  dentations,  and  the  staminate 
inflorescenses  are  1  to  2  cm.  long.    Type,  near  Tehuacan,  Puebla,  Pringle  8577  (US). 

15.  A.  TAMPiCENsis  Standley,  1.  c. — There  are  no  satisfactory  characters  upon  which  to  separate  this  from 
A .  pentandra  typica.  The  leaves  are  entire,  but  the  single  collection  thus  far  made  consists  only  of  the  ends 
of  the  branches  and  the  principal  leaves  are  therefore  unknown.  In  any  event,  this  feature  is  much  too  variable 
in  the  group  to  be  of  taxonomic  value.  The  staminate  glomerules  are  in  elongated  terminal  spikes  and  panicles, 
as  is  common  in  pentandra.  The  fruiting  bracts  are  only  2.5  to  3  mm.  long,  not  crested  but  faintly  reticulated 
on  the  faces.  The  bracts  are  therefore  undersized  for  typica,  and  in  this  respect  the  form  is  closer  to  subspecies 
muricata.    Type,  vicinity  of  Tampico,  Tamaulipas,  Palmer  332  (US). 

16.  A.  TEXANA  Watson,  Proc.  Am.  Acad.  9 :  113,  1874.— A  little-known  form  from  southern  Texas  which  may 
be  referred  to  A.  pentandra  typica  until  differentiating  characters  can  be  found.  Geographically  it  belongs 
between  typica  and  muricata,  but  the  bracts  are  much  too  large  for  the  latter,  3  to  3.5  mm.  long  by  4  to  4.5 
mm.  broad  in  the  type,  which,  however,  was  grown  in  the  botanical  garden  at  Cambridge,  Massachusetts, 
from  Texas  seed.  All  of  the  few  collections  since  made  are  from  within  250  km.  of  the  coast  of  the  Gulf  of 
Mexico.  These  localities  may  therefore  represent  the  western  limits  of  typica,  which  ranges  thence  both  north 
and  south  along  the  Gulf.  A.  texana  can  not  be  separated  from  typica  on  the  basis  of  its  entire  leaves  as  pro- 
posed by  Standley  (N.  Am.  Fl.  21 ;  37,  1916),  since  these  sometimes  are  sparingly  dentate,  as  originally  described 
by  Watson  and,  moreover,  typical  pentandra  varies  in  the  West  Indies  to  forms  in  which  the  leaves  are  nearly 
all  entire.  In  addition  to  the  type,  the  following  belong  here:  Guadalupe,  southwest  of  San  Antonio,  Texas, 
Palmer  1168  (Gr,  US);  Corpus  Christi  Bay,  Texas,  Palmer  1159  (Gr,  US);  Laredo,  Texas,  in  sandy  soil,  Rever- 
chon  3682  (Gr).     An  earlier  name  for  this  variation  is  given  under  No.  23. 

17.  A.  TUBERCULATA  Coulter,  Contr.  U.  S.  Nat.  Herb.  2 :  368,  1894.— Based  upon  Obione  elegans  tvberculosa, 
which  see  in  this  list. 

18.  A.  wARDi  Standley,  1.  c,  56,  1916.— The  types  are  nearly  leafless  plants  with  no  characters  to  differ- 
entiate them  from  typical  A.  pentandra,  except  the  absence  of  appendages  on  the  faces  of  the  fruiting  bracts. 
These  bracts  were  described  as  only  2  to  2.5  mm.  long  and  longer  than  broad.  Many  of  the  mature  ones  of 
the  type  are  fully  3  mm.  long.  The  absence  of  the  usually  broad  herbaceous  margin  is  responsible  for  this 
small  size.  The  faces  are  strongly  reticulated,  this  indicating  the  close  relationship  with  subspecies  typica 
and  arenaria.  The  root  is  annual  and  the  few  remaining  leaves  are  entire.  Type,  Galveston,  Texas,  Sep- 
tember 16,  1877,  Ward  (US). 

19.  AxYBis  PENTANDRA  Jacquin,  Sel.  Stirp.  Am.  244,  17G3.—Atriplex  pentandra  typica.  The  original 
specimen  is  illustrated  in  figure  40. 

20.  Obione  arenahia  Moquin,  Chenop.  Enum.  71,  1840.—^.  pentandra  arenaria. 

21.  O.  CRiSPA  Moquin,  1.  c,  73,  1840.— Referred  to  A.  pentandra  confinis,  although  both  leaves  and  bracts 
are  much  smaller  in  true  crispa.  According  to  Moquin,  the  leaves  in  the  type,  which  came  from  Haiti,  are 
only  0.4  to  0.6  cm.  long,  0.1  to  0.2  cm.  wide,  whitish  farinose  on  both  faces,  and  acutely  dentate,  while  the 
bracts  are  only  about  2  mm.  long.  This  very  smaD-leaved  form  is  represented  by  plants  from  Eastern  Cay, 
Turks  Island,  Bahamas  {Millspaugh  9369,  NY),  in  which,  however,  the  fruiting  bracts  are  slightly  over  3  mm. 
long.  Possibly  the  type  specimen  was  immature,  which  would  account  for  the  small  size  of  the  bracts.  The 
name  crispa  is  not  here  taken  up  because  of  the  tenable  Atriplex  crispa  Dietrich  (Syn.  PI.  5:536,  1852)  of  Asia. 

22.  O.  CRISTATA  Moquin,  1.  c. — Based  upon  Atriplex  crislata,  which  see. 

23.  O.  elegans  var.?  tuberculosa  Torrey,  Bot.  Mex.  Bound.  183,  1859.— A  form  later  described  as 
Atriplex  texana  Watson  (No.  16  of  this  list). 

24.  O.?  KUNTHIANA  Moquin,  1.  c,  72,  1840. — A.  pentandra  muricata. 

25.  0.?  MURICATA  Moquin,  in  De  CandoUe,  Prodr.  13«:109,  1849.— vl.  pentandra  muricata. 


298 


GENUS   ATRIPLEX. 
RELATIONSHIPS. 


This  is  believed  to  represent  the  plexus  from  which  a  large  series  of  species  has  origi- 
nated. At  least  7  major  species  can  be  traced  back  with  more  or  less  certainty  to  this 
stock.  They  are  all  western  and  seem  to  have  had  their  connection  through  the  sub- 
species muricata  of  Mexico.  Each  has  undergone  essential  modifications  in  one  or  more 
of  the  pentandra  characters,  and  in  every  case  the  change  has  been  in  the  direction  of  sim- 
plification or  in  the  development  of  special  features.  These  changes  will  be  indicated 
under  the  heading  of  Relationships  as  each  of  the  derived  species  is  reached.  The  hst 
includes:  elegans,  microcarpa,  wrighti,  bradeosa,  linifolia,  fruticulosa,  and  couUeri.     It  is 

I   a.arertgri3   J 

Us.  broadly  elliptic  \0 
ovate ;  bracts  *-6  mm. 
long,  N.Atlantic 
'Coast 


Lvs.  elliptic  to  lanceo- 
late or  linear  J  bracts 
3-'.mm.  long  (rarely 
A.5).  S.  Atlantic  and 
Gulf  coasts  and  West 


j   d.mi/ricafa   j 


Bracts  2.5- 3  mm.  long 
(rarely  3.EJ,  mostly  crested 
but  sometime©  smooth, 
not  strongly  reticulated; 
lvs.  greener  above " 


Bracts  about  a  mm,  long 
no  crests,  faintly  reticu- 
lated; lvs,  broadly  elKpt.< 
densely  ^hlte-scurfy 
both  sides,  crisp. 
West  Indies 


Bracts  3-6  mm.  long, 
mostly  crested, reticulated; 
lvs.  greener  above 


Fig.  41. — Phylogenetic  chart  of  the  subspecies  of  AtripUx  penlandra. 

probable  that  A.  barclayana  should  be  added  to  the  list.  If  this  is  done  pentandra  will 
then  stand  near  the  base  also  of  the  large  phylogenetic  branch  of  dioecious  shrubs,  for 
barclayana  seems  to  be  a  lateral  branch  which  sprang  from  the  common  stock  of  this 
group.  It  is  also  po.ssible  that  the  present  species  is  basal  to  the  pusilla,  truncata,  and 
argentea  groups,  but  for  a  number  of  reasons,  the  most  important  of  which  is  a  modifica- 
tion in  the  shape  of  the  fruiting  bracts  combined  with  a  rather  well-developed  separation 
of  the  sexes,  it  is  given  a  position  in  the  chart  (fig.  29,  p.  238)  superior  to  these. 

Evolution  within  the  collective  species  A.  pentandra  has  progressed  to  a  high  stage. 
The  result  is  a  number  of  subspecies  well  separated  in  their  extremes,  yet  held  together 
by  a  series  of  intergrading  forms.  Two  principal  branches  are  noted,  an  eastern  and 
a  western.     The  former  comprises  two  groups  of  forms  assembled  under  the  subspecific 


PENTANDRA. 


299 


names  arenaria  and  typica.  Subspecies  arenaria  is  perhaps  the  more  primitive,  as  sug- 
gested by  the  absence  of  reduction  in  the  leaves  and  bracts.  It  has  migrated  far  north- 
ward and  is  now  restricted  to  the  proximity  of  the  coast  from  the  Carolinas,  or  somewhat 
farther  southward,  to  New  England.  Every  attempt  made  to  separate  this  specifically 
has  failed  because  of  the  large  series  of  variations  in  all  essential  characters  in  subspecies 


Table  26. — Variation  in  the  fruiting  bracts  of  the  subspecies  of  Atriplex  pentandra. 


Surface  of  bracts. 


Subspecies  i 

Atlantic  City,  N.  J 

Long  Island,  N.  Y.  (.Clute  SZ4)- 

Groton,  Conn.  (Bissell) 

Rhode  Island  (Olney) 


Westport,  Mass 

Seaview,  Mass.  (Williams) . 
Katama  Bay,  Mass 


NY 
NY 
Gr 
Gr 

7151  UC 

Gr 

78934  UC 


5.5to6.0 

5.0 

4.5       5.0 

4.0       5.0 


6.0t«7.0 
5.0 
4.0 

4.0       6.0 


5.5      5.0       7.0 
4.2  4.2 

SO      4.0       6.0 


Average. 


.  typica: 

Swan  Island,  Honduras 

Hort.  Cantab.' 

Near  Tampico,  Mex.  (Palmer  SSS)' 

Breton  Island,  La.  (Tract/  and  Lloyd  4S). 


Miami,  Fla.  (Garber) 

Indian  River,  Fla.  (Curtiss  $367) 

Curacao  (Britlon  and  Shafer  2926) 

Porto  Rico  (Britlon  4714) 

Porto  Rico  (Sintensis  S9S6) 

Matanzas,  Cuba  (Brilton  and  Wilson  BS) 

Grand  Turk,  Bahamas  (Millspaugh  8998) .  . . 

Little  Creek,  Andros,  Bahamas  (Brace  6300) 

Water  Key,  Bahamas  (Wihon  8166) 

Atwood  Key,  Bahamas  (Wilson  74SS) 


Subspecies  d.  muricata: 
Mexico  City.  ...... 


Mexico  (Palmer  1166)*. 
Near  Tehuacan,  Puebla 
Saltillo,  Coahuila 


Gr 

Gr 

463276  US 

Gr 

Gr 
Gr 

NY 
NY 
Gr 
NY 

NY 

NY 
NY 

NY 


4.0 
2.8  3.5 
2.5       3.0 

3.5  4.0 

4.0       4.5 

3.6  3.7 
4.0 
3.5 
3.5 
4.0 


4.0 
4.0  4.5 
3.0       3.5 

3.5 

4.0  5.0 
4.0  4.8 
4.5  5.0 
4.8 
4.5 
4.0 
5.0 

5.0  6.0 
4.0 
4.2 


Smooth,  reticulated. 
Crested,  reticulated. 

Do. 
Low-crested  to  smooth, 

ulated. 
Crested,  reticulated. 

Do. 

Do. 


Not  crested,  reticulated. 
Crested, reticulations  covered. 
Not  crested,  reticulated. 
Crested   or   smooth,   reticu- 
lated. 
Crested,  reticulated. 

Do. 
Crests  covering  surface. 

Do. 

Do. 

Do. 
Crested   c 
lated. 

Do. 


smooth,    reticu- 


Do. 


Crested,  reticulated. 


11037  UC 

48301  US 


Guaymas,  Sonera  (Palmer  119)^. 
Average 


2 , 8  2-crested     to     smooth,     not 
reticulated. 

2.8  I               3.0  i  Smooth,  3-nerved. 

3.5  !  3.5       4.0  !  3-nerved. 

3.0  [  3.0       4.0  ;  2-crested     to     smooth,     not 

I                        I  reticulated. 

2.8  ;               2.8  Nearly  smooth,  3-nerved. 


'  Type  of  A.  lexana  Watson,  minor  variation  16. 

I  Type  of  A.  tampiccnsis  Standley,  minor  variation  15. 

'  Type  of  A.  glomerala  Watson,  minor  variation  9. 


«  Type  of  A.  pueblensis  Standley,  minor 
'  Doubtfully  determined. 


typica  of  the  Gulf  Coast  and  West  Indies.  The  acceptance  of  arenaria  as  a  species  would 
necessitate  the  use  of  criteria  so  trivial  that  consistency  would  demand  the  setting  up 
of  a  considerable  number  of  other  species  from  what  is  here  described  as  subspecies 
typica.  Those  best  acquainted  with  the  variations  of  typica,  especially  in  the  West 
Indies,  advise  against  treating  these  as  species  and  the  collections  already  available 
indicate  that  such  a  course  would  lead  only  to  confusion.  A  few  species  have  been 
described  from  this  group.  These  are  accounted  for  among  the  minor  variations,  where 
the  value  of  their  characters  is  briefly  discussed.     The  type  of  pentandra  is  a  small,  den- 


300  GENUS    ATRIPLEX. 

tate-leaved  plant  with  the  staminate  glomerules  much  reduced,  as  will  be  seen  from  the 
tracing  presented  here  of  the  rare  original  plate  (see  fig.  40).  The  only  variation  suffi- 
ciently distinct  to  justify  particular  mention  is  the  one  here  described  as  subspecies 
confinis  (Standley). 

The  western  branch  of  A.  pentandra  constitutes  the  single  subspecies  muricata.  This 
has  undergone  a  reduction  in  the  size  of  the  bracts  and  the  reticulations  of  these  are  less 
evident.  But  in  all  other  characters  its  equivalent  in  the  area  of  typica  is  frequently 
encountered.  Even  the  size  of  the  bracts  overlaps  in  the  two  subspecies,  as  is  indicated 
by  the  measurements  given  in  table  26.  It  was  through  subspecies  muricata,  or  some 
similar  form  perhaps  now  extinct,  that  the  7  or  more  far-western  species  of  the  pentandra 
group  were  derived. 

ECOLOGY  AND  USES. 

Atriplex  pentandra  and  its  subspecies  are  largely  tropical  and  subtropical,  and  nothing 
is  known  of  their  ecology  or  uses. 

26.  ATRIPLEX  ELEGANS  (Moquin)  Dietrich,  Syn.  PI.  5:537,  1852.     Plate  46. 
Wheelscale. 

Erect  or  subdecumbent  annual  herb,  1  to  6  dm.  high,  branched  from  the  base,  the 
branches  usually  erect  or  ascending  but  sometimes  shortly  spreading  and  the  ends  erect, 
the  whole  plant  rounded  and  bushy;  branches  slender  or  stout,  more  or  less  obtusely 
angled,  coarsely  f urf  uraceous,  glabrate  and  then  stramineous,  the  bark  persistent ;  leaves 
alternate  except  a  few  basal  pairs,  sessile  or  short-petioled,  elliptic-spatulate,  oblanceo- 
late  or  oblong  or  in  small  plants  sometimes  elliptic  or  obovate,  narrowed  to  the  base, 
obtuse  or  acute  at  apex,  0.5  to  2.5  cm.  long,  0.2  to  0.7  cm.  wide,  entire  or  remotely  and 
acutely  short-dentate,  thin,  white-furfuraceous  on  both  sides  or  sparsely  furfuraceous 
and  green  above,  only  the  midvein  prominent;  flowers  monoecious,  all  in  small  axillary 
clusters  the  lower  of  which  are  purely  pistillate,  the  upper  mixed  or  perhaps  some  near 
the  ends  of  the  branches  purely  staminate;  perianth  of  staminate  flowers  4-  or  5-cleft  or 
exceptionally  3-cleft,  of  pistillate  flowers  wanting;  fruiting  bracts  short-pedicellate, 
strongly  compressed,  united  throughout  (except  the  herbaceous  margins),  orbicular,  2  to 
4  mm.  in  diameter,  the  margins  acutely  dentate  all  around,  the  terminal  tooth  sometimes 
more  prominent  than  the  others,  the  faces  either  flat  and  unappendaged  or  with  a  single 
low  tubercle  midway  of  the  midvein  or  each  face  bearing  2  laciniate  crests  (only  in  minor 
variation  2,  variety  thornberi  Jones),  scurfy  when  young,  glabrate,  only  the  midvein 
prominent;  seed  1  to  1.4  mm.  long,  pale  to  dark  brown;  radicle  superior.  {Obione  ele- 
gans  Moquin,  in  DeCandoUe,  Prodr.  IS^illS,  1849.)  Southwestern  United  States  and 
northern  Mexico. 

SUBSPECIES. 
Atriplex  elegans  exhibits  a  natural  divergence  into  two  subspecies,  each  occupying  its 
own  geographic  area.     In  addition  to  these  there  is  a  form  here  listed  as  minor  varia- 
tion 2,  which  should  perhaps  be  subspecifically  treated. 

Key  to  the  Subspecies  of  Atriplex  elegans. 
Fruitine  bracts  with  broad  deeply  dentate  margins;  leaves  often  dentate.     Southern  Arizona 

and  eastward (o)  typica  (p.  300). 

Fruiting  bracts  with  very  narrow  shallowly  dentate  margins;  leaves  entire.     California  and 

western  Arizona (6)  fasdculata  (p.  301). 

26o.  Atriplex  elegans  typica. — Plant  usually  1.5  to  6  dm.  high;  leaves  elongated, 
1  to  2.5  cm.  long,  entire  to  saliently  denticulate;  fruiting  bracts  with  a  broad  herbaceous 
border  which  is  sharply  toothed  or  laciniate,  the  teeth  1  mm.  long  when  well  developed. 
(Obione  elegans  Moquin  in  De  Candolle,  Prodr.  13^ :  1 13,  1849.)  Western  Texas  to  south- 
ern Arizona,  eastern  border  of  Cahfornia,  Sonora,  and  Chihuahua.  Type  locality, 
Sonora.     Collections:  El  Paso,  Texas,  Jones  4171  (Gr,  US) ;  Mesilla  Valley,  New  Mexico, 


A.    ELEGANS.  301 

September  29,  1906,  Wooton  and  Standley  (NY,  US);  Arizona:  Tucson,  Thornber  131, 
197a  (UC,  form  intermediate  to  subspecies  fasciculata) ;  Santa  Cruz  Valley,  Tucson, 
August  16,  1901,  Thornber  (UC,  minor  variation  2,  var.  thornberi  Jones);  southern 
Arizona,  near  the  Mexican  Boundary,  August  7,  1884,  Pringle  (US,  same  variation); 
Maricopa,  Hall  11202a  (UC,  collected  with  11202b,  which  is  minor  variation  2,  variety 
thornberi  Jones);  Phoenix,  Griffiths  UIO  (US);  Yuma,  September  8,  1907,  Barter  (Gr, 
NY,  US) ;  Needles,  eastern  California,  Eastwood  5966  (SF) ;  Guaymas,  Sonora,  Palmer 
122  (Gr,  NY,  UC);  Gila  River,  northern  Sonora,  May,  Schott  (NY,  type  of  Obione  radi- 
ata,  minor  variation  8) ;  plains  near  Chihuahua  City,  Pringle  670  (Gr,  NY) ;  near  Durango 
City,  Palmer  ^97  (UC). 

266.  Atriplex  elegans  fasciculata  (Watson). — Plant  commonly  small,  0.5  to  3  dm. 
high,  rarely  more;  leaves  0.5  to  2  cm.  long,  entire;  fruiting  bracts  with  a  very  narrow  her- 
baceous border  which  is  minutely  toothed  or  nearly  entire.  {A.  fasciculata  Watson, 
Proc.  Am.  Acad.  17:377,  1882.)  Southern  California,  from  central  Inyo  County  south 
across  the  Mojave  and  Colorado  Deserts  to  the  borders  of  Lower  CaUfornia  and  western 
Arizona;  abundant  on  the  Colorado  Desert.  Type  locality,  near  Fish  Ponds,  Mojave 
Desert.  Collections:  California:  between  Keeler  and  Darwin,  Inyo  County,  Coville 
and  Funston  903  (DS,  US);  type  collection.  May,  1882,  Parish  1351  (Gr,  US);  Manix, 
San  Bernardino  County,  Parish  10368  (UC);  Barstow,  Mojave  Desert,  Brandegee  (UC); 
Rabbit  Springs,  Mojave  Desert,  Parish  5010  (DS,  UC) ;  Borregos  Springs,  western  edge  of 
Colorado  Desert,  May  28,  1894  and  May,  1899,  Brandegee  (UC);  Cameron  Lake,  Colo- 
rado Desert,  March  29,  1901,  Brandegee  (UC);  Cariso  Creek,  Colorado  Desert,  April, 
1905,  Brandegee  (US);  alkaline  soil,  about  60  m.  below  sea-level,  Mecca,  Colorado 
Desert,  Parish  8452  (DS,  type  of  A.  saltonensis  Parish,  minor  variation  4);  Niland, 
Imperial  Valley,  Parish  10869  (UC);  Blue  Lake,  Imperial  Valley,  Davy  8019  (UC); 
bottom  lands  along  the  Colorado  River,  near  Paloverde,  Hall  5924  (UC);  Calexico, 
Imperial  County,  Davy  7992  (UC);  low  hill  near  Volcano  Lake,  northern  Lower  Cali- 
fornia, MacDougal  196  (NY);  Phoenix,  Arizona,  Eastwood  6147  (SF);  Agua  Caliente, 
Arizona,  March  3,  1894,  Carlson  (SF);  near  San  Xavier  Mission,  south  of  Tucson, 
Arizona,  Harris  I4I8I  (US). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Atriplex  elegans  var.  fasciculata  Jones,  Contr.  West.  Bot.  12:76,  1908. — A.  elegans  subsp.  fasci- 
cidcUa. 

2.  A.  ELEGANS  var.  thornberi  Jones,  1.  c. — Characters  as  in  subspecies  typica,  except  that  each  fruiting 
bract  bears  2  prominent  lacerate  appendages  on  the  face  near  the  base.  The  margin  also  is  more  deeply 
toothed  than  usual.  The  presence  of  appendages  is  a  more  important  character  in  this  species  than  in  most 
Atriplexes,  where  it  is  known  to  be  extremely  variable.  Of  12  herbarium  sheets  examined,  all  have  either 
uniformly  smooth  or  uniformly  crested  bracts,  with  three  exceptions,  in  which  both  forms  were  found  on  the 
same  plant.  At  Tucson  and  at  Maricopa,  both  in  Arizona,  the  two  forms  grow  intermingled,  but  apparently 
with  no  intergradation  or  with  any  mixing  of  the  two  kinds  of  bracts  on  the  same  plant.  The  three  exceptions 
just  mentioned  are:  (1)  a  sheet  in  the  M.  E.  Jones  Herbarium  from  Tucson  (August  17,  1903,  Jones)  in  which 
some  of  the  bracts  are  smooth  on  the  faces  except  for  the  strong  midrib  while  others  on  the  same  stem  are 
prominently  two-crested;  and  (2  and  3)  two  sheets  in  the  United  States  National  Herbarium  from  Phoenix 
(Griffiths  4410  and  6198)  in  which  the  bracts  are  mostly  crested,  but  a  few  on  the  same  stems  without  crests 
(fig.  42,  /,  g).    The  type  locality  of  variety  thornberi  is  Tucson,  Arizona. 

3.  A.  FASCICULATA  VVatson,  Proc.  Am.  Acad.  17:377,  1882. — A.  elegans  fascic  data. 

4.  A.  SALTONENSIS  Parish;  Muhlenbergia  9 :  57,  1913. — This  is  a  common  depressed  form  of  subspecies  faa- 
ciculata,  in  which  the  short  stems  are  subdecumbent  and  the  leaves  only  0.5  to  1  cm.  long.  The  type  specimens 
are  1  to  1.5  dm.  long.  Although  fasciculata  is  often  larger  and  more  nearly  erect  than  saltonensis,  the  two 
types  are  not  very  different.  The  type  of  the  former,  as  at  the  Gray  Herbarium,  is  1  dm.  high,  the  leaves 
are  0.8  to  1.3  cm.  long,  and  the  two  main  branches  spread  horizontally  from  the  summit  of  the  taproot  to  a 
distance  of  1.5  cm.,  from  which  distance  they  are  abruptly  ascending.  The  type  locality  of  saUonensis  ia  in 
alkaline  soil  a  little  north  of  Mecca,  California. 


302 


GENUS   ATRIPLEX. 


5.  A.  THORJfBERi  Standley,  N.  Am.  Fl.  21 :57,  1916. — Based  upon  A.  elegans  thornheri,  which  see. 

6.  Obione  elegans  Moquin,  in  De  Candolle,  Prodr.  13^:  113,  1849. — A.  elegans  lypica. 

7.  0.  ELEGANS  var.?  radiata  Torrey,  Bot.  Mex.  Bound.  Surv.  183,  1859. — The  Thurber  plant  mentioned 
with  the  description  has  not  been  seen,  but  Wright  571,  from  western  Texas,  is  A.  elegans  typica  with  rather 
deep  incisions  in  the  margins  of  the  fruiting  bracts.  The  original  radiata  of  Torrey  also  included  plants  refer- 
able to  A.  wrighti,  according  to  Coulter  (Contr.  U.  S.  Nat.  Herb.  2:368,  1894). 

8.  0.  RADLATA  Torrey,  1.  c. — Not  distinguishable  from  A.  elegans  typica.  Type  locality,  alluvions  of  the 
Gila  River,  northern  Sonora. 


Fio.  42. — Fruiting  bracts  of  Alriplex  elegam:  a,  b,  e,  /,  g,  subspecies  typica;  d,  e,  subspecies  fasciculala;  a,  from  Durango 
(110218  UC);  b,  from  Tucson,  Arizona  (128540  UC);  c,  from  Tucson,  Arizona  (7167  UC);  d,  from  the  Colorado 
Desert,  California  (110328  UC);  e,  from  the  Mojave  Desert,  California  (type  of  fasciculala,  Gr);  /,  g,  from  a 
single  plant  from  Phoenix,  Arizona  (424737  US).     All  X  6. 

RELATIONSHIPS. 

The  development  of  this  species  from  the  aggregate  known  as  A.  pentandra  is  quite 
certain.  It  appears  to  be  a  derivative  of  some  form  near  to  the  primitive  subspecies 
muricata  which  has  become  modified,  especially  in  its  bracts.  These  have  been  strongly 
compressed  and  the  marginal  dentations  regularly  spaced,  while  the  staminate  terminal 
spikes  have  been  almost  entirely  suppressed,  the  flowers  being  confined  in  elegans  to  the 
leaf-axils.  From  this  point  of  view,  the  present  species  is  a  northwestern  derivative, 
which  theory  gains  support  from  the  close  similarity  between  specimens  of  muricata  from 
the  northern  borders  of  its  area  and  some  of  elegans  from  adjacent  territory  (e.  g..  Palmer 
290,  representing  the  former,  and  Palmer  J^97,  representing  the  latter,  both  from  near 
Durango).  Such  plants  are  almost  identical,  except  in  the  features  mentioned.  Fur- 
thermore, the  differences  become  more  pronounced  at  greater  distances  from  the  ances- 
tral home  in  Mexico.  Thus,  the  bract  appendages,  so  peculiarly  developed  in  muricata, 
are  still  present  in  a  form  of  elegans  known  as  variety  thornheri  (minor  variation  2), 
which  is  most  plentiful  in  northern  Sonora  and  southern  Arizona,  while  the  bracts 
are  always  smooth  in  subspecies /asacwZaia,  a  form  of  the  Californian  deserts.  Thus  the 
connections  with  pentandra  through  its  subspecies  muricata  (or  possibly  the  little-known 
minor  variation  cyclostegia)  may  be  traced  along  a  line  that  is  also  the  route  over  which 
the  forms  have  passed  in  their  northwestward  migrations. 

Although  this  species  has  given  rise  to  no  others,  and  is  therefore  represented  as  at 
the  end  of  a  line  on  the  phylogenetic  chart,  it  is  by  no  means  stationary.  This  is  evi- 
denced by  several  forms  within  the  species,  the  best-marked  of  these  being  subspecies 
fasciculala,  in  which  there  is  a  notable  reduction  in  the  width  and  dentation  of  the  margins 
of  the  fruiting  bracts.  The  leaves  and  also  the  whole  plant  are  often  but  not  always 
much  reduced  in  size.  The  leaves  are  always  entire,  as  far  as  known,  which  has  led  to 
the  use  of  this  difference  as  a  prime  character  for  specific  segregation.  But  it  is  quite 
untrustworthy,  for  not  only  are  a  portion  of  the  leaves  entire  in  typical  elegans,  but  in 
some  specimens  with  typical  bracts  apparently  all  the  leaves  are  entire  (Tucson,  Ari- 
zona, August  12,  1901,  Thornber  7164,  UC).  The  bract  character  is  therefore  taken  as 
the  more  reliable  and  the  one  which  can  best  be  correlated  with  features  of  habit  and 
distribution.  That  it  is  not  of  specific  value  may  be  seen  from  an  examination  of  the 
accompanying  plate  and  text-figures,  where  it  will  be  noted  that  all  gradations  may  easily 
be   found. 


A.    MICROCARPA.  303 

ECOLOGY  AND  USES. 

Atriplex  elegans  typically  forms  pure  or  mixed  socies  in  moderately  saline  areas  in  the 
valleys  of  southern  Arizona,  where  it  is  associated  with  A.  canescens  or  A.  polycarpa,  or 
both.  Recently  it  has  become  a  common  weed  in  roadsides,  fallow  fields,  and  other  dis- 
turbed places,  serving  as  a  pioneer  of  a  short  secondary  succession.  Kearney  and  his 
associates  found  as  much  as  1  per  cent  of  salt  in  the  first  foot  of  soil,  and  0.67  per  cent 
in  the  second.  It  flowers  regularly  after  the  summer  rains,  but  it  may  also  bloom  in  late 
spring  as  a  consequence  of  abundant  rainfall. 

This  species  furnishes  excellent  grazing,  but  is  limited  in  amount.  According  to 
Thornber,  it  is  used  as  greens  by  the  Pima  Indians,  and  it  is  probably  a  cause  of  hay- 
fever  to  some  extent. 

27.  ATRIPLEX  MICROCARPA  (Bentham)  Dietrich,  Syn.  PI.  5:  536, 1852.     Plate  48. 

DOTSCALE. 

Prostrate  or  procumbent  annual  herb,  commonly  much  branched  to  form  tangled 
masses  2  to  10  dm.  across  and  1  to  4  dm.  high,  the  ultimate  branches  ascending  or  erect; 
sometimes  less  branched  and  all  of  the  stems  ascending;  branches  tough,  flexuous, 
obtusely  angled  or  terete,  lightly  furfuraceous  when  young,  very  soon  glabrate  and  then 
stramineous,  the  bark  persistent,  breaking  only  on  old  stems;  leaves  alternate  or  a  few 
lower  ones  opposite,  numerous,  sessile  or  the  lower  short-petioled,  oblanceolate  or  spatu- 
late-elliptic,  narrowed  at  base,  acute  or  obtuse  at  apex,  often  mucronulate,  0.5  to  2  cm. 
long,  0.3  to  0.6  cm.  wide,  entire,  thin,  sparsely  scurfy  and  green  above,  more  closely 
scurfy  and  gray  beneath,  l-nerved;  flowers  monoecious,  the  staminate  glomerules  in 
the  upper  axils  or  rarely  a  few  of  the  upper  glomerules  without  subtending  leaves  and 
thus  short-spicate,  the  pistillate  also  in  axillary  glomerules,  but  these  beneath  the  stam- 
inate, many  of  the  intermediate  glomerules  with  both  staminate  and  pistillate  flowers; 
perianth  deeply  5-cleft  in  the  staminate  flowers,  wanting  in  the  pistillate;  fruiting  bracts 
sessile  or  very  shortly  stalked,  not  compressed,  united  nearly  to  the  summit,  nearly  orbic- 
ular, but  with  narrowed  base  and  broad  summit,  obtuse,  1  to  2  mm.  long,  1  to  2.2  mm. 
broad  (larger  in  minor  variation  3),  entire,  except  for  1  to  several  minute  teeth  across  the 
summit,  faces  smooth  or  with  a  few  minute  tubercles,  l-nerved,  not  obviously  reticulated; 
seed  0.8  mm.  long,  light  brown;  radicle  superior.  {Obione  microcarpa  Bentham,  Bot. 
Voy.  Sulph.  48,  1844.  Not  A.  microcarpa  Waldstein  and  Kitaibel,  1812,  nor  A.  micro- 
carpa Bentham,   1870.) 

Near  the  coast  from  Los  Angeles  County,  California,  to  middle  western  Lower  CaUfor- 
nia,  including  the  adjacent  islands.  Type  locality,  San  Diego,  California.  Collections, 
all  in  California  and  Lower  California:  San  Pedro  Hills,  near  Rocky  Point,  Los  Angeles 
County,  Abrams  3137  (DS,  NY,  UC,  US);  Redondo,  Los  Angeles  County,  October  15, 
1903,  Brandegee  (UC);  Avalon,  Santa  Catalina  Island,  March,  1901,  Trask  (NY,  US); 
San  Clemente  Island,  April  26,  1912,  Wooton  (US);  Laguna  Beach,  Orange  County, 
May  5,  1916,  Crawford  (UC);  La  Jolla,  near  San  Diego,  Clements  59  (Gr,  UC);  San 
Diego,  Palmer  330  (Gr,  NY);  San  Quentin  Bay,  Palmer  717  (Gr,  US);  Cedros  Island, 
Palmer  755  (Gr,  NY,  US).  Other  stations  for  Lower  California  are  given  under  minor 
variation  3. 

MINOR  VARIATIONS  AND  SYNONYMS. 

The  characters  of  this  species  are  remarkably  constant,  there  being  but  little  fluctuation,  even  in  the  vege- 
tative features.  This  constancy  is  a  common  characteristic  of  species  of  limited  distribution.  The  only 
variation  of  note  is  the  large-bracted  form  found  near  the  southernmost  Umits  of  the  area  inhabited  and 
described  under  No.  3. 

1.  Atriplex  pacifica  Nelson,  Proc.  Biol.  Soc.  Wash.  17:99,  1904.— The  correct  name  for  those  who  follow 
the  American  rules.  According  to  these  rules  the  name  A.  microcarpa  (Bentham)  Dietrich  can  not  be  used 
for  this  plant  because  of  the  earlier  A.  microcarpa  Waldstein  and  Kitaibel  (P.  Rar.  Hung.  3:278,  1812).  This 
latter,  however,  is  generally  considered  as  synonymous  with  A.  patula  hastata,  or  at  most  only  a  minor  variation 
of  this. 


304  GENUS   ATRIPLEX. 

2.  Obione  microcarpa  Bentham,  Bot.  Voy.  Sulph.  48,  1844.—^.  microcarpa  Dietrich. 

3. — A  very  distinct  form  or  subspecies,  apparently  connecting  with  A.  pentandra  muricata,  of  Mexico,  comes 
from  Lower  California  and  the  islands  to  the  west.  This  is  a  small  annual  with  prostrate  lower  branches, 
narrowly  spatulate  leaves,  and  fruiting  bracts  sometimes  as  much  as  4  mm.  long  through  the  development  of 
a  prominent  terminal  lobe,  or  tooth.  Most  of  the  bracts,  however,  even  on  the  same  plant,  are  only  about 
2  mm.  long  and  exactly  like  bracts  of  the  common  form  of  microcarpa.  This  variation  apparently  is  well 
isolated  geographically  from  the  more  northern  type.  Collections  at  hand  include:  Natividad  Island,  April 
10,  1897,  Brandegee  (UC);  San  Benito  Island,  Anthony  877  (DS,  UC,  US);  San  Jose  de  Gracia,  April  8,  1889, 
Brandegee  (UC). 

RELATIONSHIPS. 

All  available  evidence  indicates  that  this  is  a  derivative  of  A.  pentandra  through  its 
Mexican  subspecies  muricata.  The  two  are  identical  in  essential  features,  such  as  posi- 
tion of  embryo,  distribution  of  the  two  kinds  of  flowers,  and  general  shape  of  bracts  and 
leaves.  A.  microcarpa  exhibits  the  greater  specialization,  especially  in  the  almost  con- 
stantly reduced  staminate  inflorescence,  reduced  size  of  bracts  and  leaves,  more  uniform 
suppression  of  bract-margins  and  bract-appendages,  and  constantly  annual  habit.  These 
modifications  apparently  arose  in  connection  with  the  northwesterly  migration  of  the 
group.  Genuine  muricata  stops  at  the  western  shores  of  the  Sonoran  Coast;  microcarpa 
now  begins  about  half-way  up  the  peninsula  of  Lower  California,  on  the  Pacific  side,  and 
ranges  thence  northward.  The  connection  between  the  two  seems  to  be  established  by 
minor  variation  3  of  the  latter  species,  which  comes  from  that  portion  of  the  range  of 
microcarpa  which  is  nearest  to  that  of  muricata.  The  reductions  indicated  above  are 
mostly  quite  evident  in  this,  except  that  the  staminate  inflorescence  sometimes  is  even 
more  elongated  than  in  any  known  form  of  muricata  and  some  of  the  bracts  also  are  as 
in  muricata,  while  the  leaves  are  intermediate  and  with  their  own  pecuUar  shape.  How- 
ever, the  elongated  inflorescence  is  a  feature  of  only  one  of  the  twelve  plants  at  hand  and 
may  be  either  abnormal  or  a  development  representing  a  local  strain.  In  other  plants 
of  the  same  collection  (Natividad  Island,  Brandegee)  the  staminate  glomerules  are  all 
axillary.  The  bracts  on  this  intermediate  form  vary  all  the  way  from  broadly  winged, 
and  therefore  as  large  as  in  muricata,  to  nearly  wingless  and  as  small  as  in  microcarpa. 
Most  of  them  are  of  this  latter  type  and  the  sides  are  not  appendaged. 

The  phylogenetic  connection  just  discussed  was  first  suggested  by  Bentham  in  con- 
nection with  his  original  description  of  the  species.  Bentham  attempted  to  include  also 
A.  barclayana  in  the  group,  the  material  then  available  giving  no  indication  that  this 
species  was  chiefly  dioecious,  as  has  been  since  established.  Other  features  also  now 
indicate  that,  while  A.  barclayana  belongs  somewhere  near,  it  is  better  considered  as  a 
divergent  line  which  stands  close  to  the  beginning  of  a  large  group  of  species  character- 
ized by  a  shrubby  and  dioecious  habit.  There  is  now  no  reason  to  suppose  that  micro- 
carpa evolved  by  the  roundabout  route  of  barclayana,  and,  moreover,  there  would  be 
several  insurmountable  objections  to  such  a  theory. 

ECOLOGY  AND  USES. 

Atriplex  microcarpa  forms  small  clan-like  groups  in  sandy  soil  back  of  the  strand,  and 
occurs  also  as  a  subruderal  along  roadsides.  The  flowers  open  for  the  most  part  from 
March  to  June,  but  have  been  found  as  late  as  October. 

No  uses  are  known  for  this  species,  though  it  is  possibly  an  occasional  cause  of  hay- 
fever, 

28.  ATRIPLEX  WRIGHT!  Watson,  Proc.  Am.  Acad.  9: 113,  1874.    Plate  47. 

Erect  or  ascending  annual  herb,  2  to  8  dm.  high,  the  branches  few  and  the  plants  bush- 
like; branches  thick,  deeply  grooved,  sparsely  scurfy,  soon  glabrate  and  then  stramineous 
or  reddish;  leaves  alternate,  numerous,  mostly  short-petioled,  oblanceolate  to  elliptic- 
spatulate,  all  much  narrowed  to  the  base,  obtuse  and  mucronulate  or  the  upper  ones 


A.    WRIGHTI — A.    BRACTEOSA.  305 

acute  at  apex,  2  to  7  cm.  long,  0.5  to  2.5  cm.  wide,  coarsely  sinuate-dentate  or  repand- 
dentate  or  many  of  the  leaves  entire,  thin,  sparsely  scurfy  but  soon  glabrate  and  green 
on  the  upper  surface,  permanently  white-scurfy  beneath,  strongly  1 -nerved;  flowers 
monoecious,  the  staminate  glomerules  in  naked  terminal  panicles  5  to  30  cm.  long,  the 
pistillate  flowers  in  nearly  all  of  the  leaf -axils;  perianth  5-cleft  in  the  staminate  flowers, 
wanting  in  the  pistillate;  fruiting  bracts  short-stalked  or  sessile,  well  compressed,  united 
to  about  the  middle,  euneate-orbicular,  2  to  3  mm.  long,  2.5  to  4  mm.  broad,  the  con- 
spicuous margins  greenish  above  the  middle  and  acutely  gash-toothed,  the  faces  usually 
not  appendaged,  but  with  3  nerves  from  the  base;  seed  1.2  to  1.5  mm.  long,  brown; 
radicle  superior. 

Southwestern  New  Mexico,  Arizona,  and  northern  Sonora.  Type  locality.  New  Mex- 
ico. Collections:  Type  collection,  Wright  1743  (Gr,  NY) ;  Mangas  Springs,  Grant  County, 
New  Mexico,  Metcalfe  639  (NY,  US) ;  Grain's  Ranch,  northwestern  Grant  County,  New 
Mexico,  July  18,  1900,  Wooton  (US);  Old  Camp  Goodwin,  Arizona,  Rothrock  343  (US); 
Clifton,  Arizona,  Davidson  2937  (US) ;  Williams,  Arizona,  Griffiths  4924  (US) ;  cultivated 
lands  at  Tempe,  Arizona,  Kearney  96  (US) ;  Santa  Cruz  Valley,  Tucson,  Arizona,  Thorn- 
ier 134  (UC) ;  Catalpa,  Arizona,  MacDougal  749  (US). 

SYNONYM. 

1.  Atriplex  radiata  Coulter,  Contr.  U.  S.  Nat.  Herb.  2:368,  1894.— Intended  by  Coulter  to  replace  the 
name  A.  wrighti,  because  of  the  earlier  Obione  elegans  radiata  Torrey.  But  Torrey's  name,  in  addition  to 
having  only  varietal  rank,  is  not  now  desirable,  since  it  covered  plants  of  A.  elegans  as  well  as  of  ^.  tvTighii, 
and,  moreover,  its  descriptive  features  are  misleading  for  the  present  species. 

RELATIONSHIPS. 

Atriplex  wrighti  stands  between  A.  pentandra  muricata  and  A.  bracteosa,  both  geograph- 
ically and  phylogenetically.  Its  origin  from  the  former  or  from  some  slightly  more  prim- 
itive ancestral  stock  seems  reasonably  certain.  It  has  a  closely  similar  habit.  The 
fruiting  bracts  are  slightly  reduced  in  size  but  retain  the  characteristic  reticulate  vena- 
tion. The  leaves  have  modified  their  shape  and  become  for  the  most  part  broadest 
above  the  middle.  This  is  looked  upon  as  a  later  development  from  the  usual  lanceolate 
or  ovate  shape.  On  the  other  hand,  the  inflorescence  exhibits  no  reduction,  the  elongated 
staminate  panicles  being  especially  well  developed.  Since  the  inflorescences  usually  are 
much  reduced  in  muricata,  it  is  probable  that  wrighti  diverged  from  the  common  stock 
before  the  present  characters  of  the  former  were  firmly  fixed.  The  connection  with 
bracteosa  will  be  discussed  when  this  species  is  reached. 

ECOLOGY  AND  USES. 

Atriplex  wrighti  forms  dense  consocies  in  river  valleys  with  somewhat  alkaline  soil, 
often  making  pure  stands  3  to  4  feet  in  height  and  almost  impenetrable,  but  usually  asso- 
ciated with  Amarantus  palmeri  and  Eriochloa  polystachya,  and  less  commonly  with  Kal- 
stroemia  grandiflora.  It  grows  sparsely  along  roadsides  on  the  mesas,  but  becomes  a  weed 
in  valley  roads  and  in  cultivated  fields. 

The  vigorous  growth  and  palatability  of  this  species  render  it  of  considerable  value  for 
grazing,  as  indicated  by  the  fact  that  it  is  grazed  close  to  the  ground  in  dry  seasons.  It 
gives  promise  of  becoming  a  valuable  forage  plant  under  cultivation. 

29.  ATRIPLEX  BRACTEOSA  (Durand  and  Hilgard)  Watson,  Proc.  Am.  Acad.  9:115,  1874. 
Plate  47.     Bractscale. 

Erect  or  decumbent  annual  herb,  3  to  10  dm.  high,  the  stems  commonly  spreading  to 
form  dense  tangled  mats  5  to  30  dm.  across,  from  which  arise  slender  erect  or  ascending 
twigs,  or  whole  plant  erect,  slender,  and  sparsely  branched  in  some  forms  (see  minor 
variation  4) ;  branches  thick,  obtusely  angled  or  grooved,  sparsely  scurfy,  soon  glabrate 


306  GENUS   ATRIPLEX. 

and  then  pale  or  stramineous,  rarely  reddish;  leaves  alternate,  numerous,  sessile  or  sub- 
sessile,  lanceolate,  narrowly  ovate,  or  narrowly  elliptic,  all  narrowed  to  the  base,  acute 
or  acuminate  at  apex,  mostly  2  to  4  cm.  long,  0.4  to  1.5  cm.  wide,  or  up  to  8  cm.  long  by  4 
cm.  wide  on  vigorous  sterile  shoots,  acutely  and  sparingly  dentate  or  some  entire,  thin, 
scurfy  only  when  young,  equally  green  or  greenish  on  both  faces  or  only  sUghtly  paler 
beneath,  strongly  l-nerved;  flowers  monoecious,  the  staminate  glomerules  in  naked  ter- 
minal panicles  or  spikes,  these  5  to  15  cm.  long  or  occasionally  only  3  or  4  cm.  (still  more 
reduced  in  a  hybrid  form,  minor  variation  1),  the  pistillate  flowers  in  small  clusters  in 
nearly  all  of  the  leaf -axils;  perianth  apparently  always  5-cleft  in  the  staminate  flowers, 
wanting  in  the  pistillate;  fruiting  bracts  sessile  or  subsessile,  slightly  to  moderately  com- 
pressed, united  to  about  the  middle,  cuneate-orbicular  or  fan-shaped  with  a  narrowed 
summit,  2  to  2.5  or  rarely  3  mm.  long,  2  to  3  mm.  broad,  the  margins  greenish  and  acutely 
dentate  above  the  middle,  the  faces  tuberculate  or  sometimes  smooth,  l-nerved  and  with 
also  some  faint  secondary  nerves  but  not  reticulated,  scarcely  scurfy;  seed  1  to  1.3  mm. 
long,  brown;  radicle  superior.  {Obione  bradeosa  Durand  and  Hilgard,  Pacif.  R.  R.  Rep. 
5':  13,  1858.) 

Alkaline  valleys  of  California  from  the  Sacramento  Valley  south  to  the  borders  of  Lower 
California,  very  abundant  in  the  San  Joaquin  Valley  and  on  the  coastal  slope  of  southern 
California,  rare  east  of  the  Sierra  Nevada;  grows  also  in  west-central  Nevada.  Type 
locality,  Poso  Creek,  Kern  County,  California.  Collections,  all  in  California  except  the 
last  three:  Chico,  Butte  County,  Heller  13350  (SF) ;  Princeton,  Colusa  County,  Septem- 
ber 14, 1905,  Chandler  (UC) ;  east  of  Maxwell,  Colusa  County,  Hall  11011  (UC) ;  Manteca, 
San  Joaquin  County,  October  26,  1919,  Hall  (UC);  West  Park,  near  Fresno,  October  26, 

1901,  Dawes  (UC);    near  Hanford,  Tulare  County,  Kearney  153  (US);  Tulare,  August, 

1902,  Pillsbury  (UC);  Visalia,  September,  1881,  Congdon  (UC);  Rosedale,  near  Bakers- 
field,  Davy  2886  (UC);  near  Kernville,  Purpus  5537  (UC);  Lancaster,  western  part  of 
Mojave  Desert,  Elmer  3984  (DS,  Gr,  NY,  US);  Summerland,  Santa  Barbara  County, 
Abrams  41 42  (Gr,  NY);  near  Piru,  Ventura  County,  October  20,  1919,  Hall  (UC);  Santa 
Catalina  Island,  Eastwood  6529  (SF) ;  Cienega,  near  Los  Angeles,  Braunton  636  (UC,  US) ; 
near  San  Bernardino,  Pansh  21195  (UC);  near  Riverside,  Fiemeisei  3765,  3767,  3647 
(US);  near  Winchester,  Riverside  County,  April,  1902,  Hall  (UC);  Elsinore,  July  8,  1896, 
McClatchie  (UC);  San  Diego,  Vasey  554  (US);  Needles,  Eastwood  5968  (SF);  Tecate 
River,  Lower  California,  Mearns  3785  (US);  Coronado  Islands,  on  bluffs  near  the  sea. 
Lower  California,  Cowles  14  (Pomona,  minor  variation  \,  A.  davidsoni);  Reno,  Nevada, 
Petersen  466  (UC). 

MINOR  VARIATIONS  AND  SYNONYMS. 

This  species  exhibits  a  wide  range  of  vegetative  forms,  most  of  which  can  be  correlated  with  environmental 
conditions.  These  include  variations  in  size,  dentation,  and  succulence  of  leaf  and  a  wide  divergence  in  the 
habit,  this  ranging  from  nearly  simple  erect  plants  to  widely  branched  forms  which  make  tangled  masses 
2  meters  or  more  across  and  sometimes  1  meter  high.  There  is  no  indication  that  the  root  is  ever  perennial, 
as  has  been  reported.  Three  forms  which  seem  to  be  quite  different  from  the  fluctuating  variations  just 
mentioned  are  described  under  Nos.  1,  4,  and  5. 

1.  Atriplex  davidsoni  Standley,  N.  Am.  Fl.  21:57,  1916.— This  is  exactly  like  a  common  small-leaved 
form  of  A.  bradeosa,  except  that  the  terminal  staminate  spikes  are  reduced  to  very  short,  almost  globose 
terminal  clusters.  The  cause  of  this  is  not  known,  but  the  occurrence  of  the  form  only  along  the  coast  of 
southern  California,  where  A.  microcarpa  also  grows,  suggest  that  possibly  it  may  be  a  hybrid,  with  this  species 
for  the  other  parent.  A  rather  more  noticeable  compression  of  the  bracts  and  the  presence  of  3  faint  nerves 
on  each  bract  lend  support  to  this  view.  The  collections  thus  far  made  show  no  intcrgrading  series  between 
davidsoni  and  bracteosa,  but  a  single  collection  is  intermediate.  This  is  Parry  677  (US)  in  which  the  staminate 
inflorescence  varies  from  a  globoid  cluster  to  spicate  and  2  cm.  long.  Collections  of  davidsoni  include:  Type 
collections,  labeled  as  Balboa,  California,  Davidson  2951  (US)  but  said  by  Davidson  to  have  been  gathered 
between  Balboa  and  Santa  Ana;  Temple  Street,  Los  Angeles,  Braunton  680  (DS,  UC,  US);  Long  Beach,  Parish 
(DS,  US);  Mcsmer,  Abrams  206  (DS);  San  Pedro,  Eastwood  165  (SF);  Abalonc  Point,  Laguna  Beach  Bluffs, 
July  29,  Crawjmd  (Pomona,  US);  Coronado  Islands,  Crawford  14  (Pomona). 


A,    BRACTEOSA.  307 

2.  A.  8ERENANA  Nelson,  in  Abrams,  Fl.  Los  Angeles,  128,  April  5,  1904;  Proc.  Biol.  Soc.  Wash.  17 :99,  April  9, 
1904. — This  name  has  been  adopted  by  some  American  botanists  for  A.  bracteosa  Watson  because  of  the 
earlier  A.  bracteosa  Trautvetter,  Act.  Hort.  Petrop.  l':17,  1870.  This  latter  is  synonymous  with  the  still 
older  A.  dimorphostegia  Karelin  and  Kirilow,  an  Asiatic  species.  The  name  bracteosa  is  therefore  available 
for  the  American  plant,  according  to  the  International  Code. 

3.  Obione  bracteosa  Durand  and  Hilgard,  Pacif.  R.  R.  Rep.  5':  13,  1858. — A.  bracteosa  Watson. 

4. — A  slender,  strictly  erect,  early  maturing  form  of  Atriplex  bracteosa  is  sometimes  found  in  the  San  Joaquin 
Valley,  California.  It  always  grows,  as  far  as  known,  in  sod  of  Dislichlis  spicata  and  Cynodon  dactylon.  The 
foliage  is  yellow  and  sere  by  the  middle  of  October,  when  the  typical  form  in  nearby  fields  is  still  green.  No 
differences  can  be  found  in  the  fruiting  bracts  or  other  essential  characters,  and  the  assumption  is  that  it  is 
an  ecologic  or  seasonal  form.  It  is  of  some  interest  in  connection  with  the  curly-top  disease  of  the  sugar-beet, 
since  the  leaf-hopper  that  transmits  this  disease  is  not  carried  over  so  late  on  these  slender  plants  as  on  the 
usual  form.  The  following  collections  belong  here:  5  km.  northwest  of  Hanford,  Hall  10970  (UC);  near 
Fresno,  October  25,  1919,  Hall  (UC);  between  Bakersfield  and  Rosedale,  Hall  11780  (UC);  Rosedale,  Davy 
S922  (UC). 

5. — A  supposed  hybrid  between  A.  bracteosa  and  A.  argentea  expansa  has  been  collected  near  Ventura, 
California  (Hall  10964,  UC).  It  is  a  rounded,  bushy  plant  7  dm.  high  with  staminate  inflorescences  of  the 
former,  but  bracts  as  in  the  latter.  The  stems  and  branches  are  rigid,  as  in  expansa.  The  leaves  are  similar 
to  those  of  bracteosa  in  shape  and  dentation,  but  larger,  especially  broader,  and  therefore  somewhat  intermediate. 

RELATIONSHIPS. 

Atriplex  bracteosa  is  the  end  of  an  evolutionary  line  which  began  somewhere  near  A.  pen- 
tandra  and  threw  off  as  short  divergent  branches  A.  p.  muricata,  A.  barclayana,  A.  lini- 
folia,  and  A.  wrighti.  This  process  was  accompanied  by  a  migration  of  the  group  from 
the  ancestral  habitat  in  central  or  southern  Mexico  to  the  north  and  northwest.  A. 
bracteosa  is  restricted  in  its  distribution  to  California,  with  only  slight  invasions  across  the 
borders  into  Nevada  and  Lower  California.  It  is  thus  well  separated  geographically  from 
its  nearest  allies.  A.  microcarpa,  which  belongs  to  the  same  general  group,  occurs  also 
along  the  coast  of  southern  California,  but  this  arose  from  another  branch  and  reached  its 
present  location  by  way  of  Lower  California,  whereas  bracteosa  has  its  closest  affinities  with 
species  of  Arizona  and  New  Mexico.  Although  these  two  species  apparently  hybridize, 
as  is  indicated  under  minor  variation  1,  no  intermediates  occur  and  their  connection  can 
be  traced  only  through  more  primitive  Mexican  forms. 

The  nearest  approach  to  the  common  phylogenetic  stock  is  through  A.  wrighti,  which, 
however,  exhibits  certain  specialized  features  of  its  own.  A.  bracetosa  differs  from  this 
in  the  still  more  reduced  size  of  the  bracts  and  seeds,  in  the  much  less  or  scarcely  com- 
pressed fruits,  and  in  having  the  leaves  broadest  below  the  middle  and  with  smaller, 
acute  dentations.  The  foliage  is  not  white  beneath  and  the  fruiting  bracts  do  not  have 
the  3  nerves  and  fine  reticulations  which  have  been  cited  as  evidence  of  the  connection 
between  wrighti  and  muricata. 

ECOLOGY. 

Atriplex  bracteosa  was  originally  a  moderate  halophyte  of  the  Distichlis  zone  especially, 
but  in  recent  years  it  has  become  the  most  characteristic  weed  of  disturbed  areas  in  the 
San  Joaquin  Valley.  It  often  covers  fallow  fields,  roadsides,  fenceways,  etc.  with  a 
dense  pure  community.  The  plants  are  exceedingly  vigorous  and  produce  abundant 
seeds,  so  that  they  maintain  the  initial  consocies  for  a  longer  period  than  usual. 
Kearney  and  his  associates  have  found  a  range  of  no  alkali  to  0.32  per  cent  in  the  first 
foot  of  soil  and  0.2  per  cent  in  the  second  foot.     The  flowers  appear  from  April  to  October. 

USES. 

This  species  is  of  no  value,  as  it  is  not  eaten  by  stock,  but  it  is  of  some  importance  as 
a  cause  of  hay-fever.  Its  greatest  interest,  however,  is  in  connection  with  the  curly-leaf 
disease  of  the  sugar-beet.      This  malady  has  become  so  serious  in  some  of  the  western 


308  GENUS   ATRIPLEX. 

States  that  the  production  of  sugar-beets  has  been  abandoned  over  extensive  areas, 
with  the  consequent  closing  down  of  sugar  factories  in  some  districts.  The  exact  nature 
of  the  disease  is  not  known,  but  since  it  is  transmitted  exclusively  by  the  beet  leaf-hopper 
(Eutetiix  tenella  Baker),  a  knowledge  of  the  habits  of  this  insect  is  of  prime  importance. 
According  to  Severin,  after  the  beets  are  harvested  the  leaf-hoppers  pass  to  certain 
wild  species,  the  most  important  of  which  are  the  annual  Atriplexes.  When  these 
dry  up  in  the  autumn  the  insects  pass  over  to  the  shrubby  species,  especially  those 
of  the  foothill  canons,  where  they  remain  until  after  the  first  winter  rains,  when 
they  leave  these  plants  for  the  more  tender  annuals,  particularly  Erodium  cicutarium. 
The  annual  Atriplexes  are  important  as  host-plants  upon  which  Eutetiix  breeds  from 
spring  to  autumn.  Of  these,  the  most  important  are  A.  argentea  expansa,  A.  bracteosa, 
and  A.  rosea,  because  of  their  remaining  succulent  later  in  the  season  than  most  other 
species  and  because  of  their  abundance.  It  is  believed  that  the  considerable 
increase  in  the  number  of  these  plants  as  a  result  of  disturbances  due  to  man  is 
largely  responsible  for  the  enormous  number  of  leaf-hoppers.  The  most  important 
shrubby  Atriplexes  which  serve  as  food  plants  for  the  insects  in  a  dry  season  in  Cali- 
fornia are  A.  polycarpa  and  A.  spinifera. 

The  eradication  of  the  Atriplexes  is  impracticable,  because  of  their  great  abundance. 
It  is  therefore  impossible  to  control  the  disease  by  the  destruction  of  the  host-plants  of 
the  carrier.  However,  a  knowledge  of  the  distribution  and  abundance  of  the  different 
species  is  an  aid  in  determining  the  districts  where  outbreaks  of  Eutettix  are  most  likely 
to  occur.  Such  information,  therefore,  should  be  used  in  selecting  locations  for 
the  culture  of  the  sugar-beet  and  for  the  erection  of  factories.  This  subject  has  been 
discussed  in  detail  by  many  writers,  more  especially  by  Severin  and  Basinger  (Journ. 
Econ.  Ento.  15:  411-419,  1922). 

30.  ATRIPLEX  LINIFOLIA  Humboldt  and  Bonpland,  in  WiUdenow,  Sp.  PI.  4:958,  1806. 
Plate  47. 

Erect  or  decumbent  perennial  herb,  2  to  8  dm.  high,  the  stems  curving  upwards  from 
a  short  woody  base;  branches  moderately  thick,  angled  or  grooved  in  the  inflorescence, 
sparsely  scurfy,  soon  glabrate  and  then  stramineous;  leaves  alternate,  crowded,  sessile 
or  short-petioled,  linear  or  linear-oblong  or  some  narrowly  spatulate,  cuneate  to  attenu- 
ate at  the  base,  obtuse  and  mucronate  or  acutish  at  apex,  1  to  4  cm.  long,  0.2  to  0.5  cm. 
wide,  entire  or  the  larger  ones  with  a  few  spreading  teeth,  rather  thin,  glabrate  and 
greenish  on  the  upper  surface,  permanently  gray-scurfy  beneath,  1-nerved;  flowers 
monoecious  or  partly  dioecious,  the  pistillate  flowers  in  the  leaf-axils,  the  staminate 
glomerules  in  nearly  naked  terminal  spikes  and  panicles,  these  5  to  15  cm.  long;  perianth 
5-cleft  in  staminate  flowers,  wanting  in  the  pistillate;  fruiting  bracts  sessile  or  short- 
stalked,  compressed,  united  to  above  the  middle,  cuneate-orbicular,  the  summit  always 
broadly  rounded,  2  to  2.5  mm.  long,  2.5  to  3  mm.  broad,  the  margins  obtusely  or  acutely 
dentate  above  the  middle,  the  faces  either  tuberculate  or  crested  or  unappendaged  on 
the  same  plant  and  reticulated  or  the  reticulations  masked  by  the  appendages,  scarcely 
scurfy;  seed  about  1.2  mm.  long,  brown;  radicle  superior. 

Mexico,  apparently  rare.  Type  locality,  Mexico.  Collections :  Vicinity  of  Durango, 
Palmer  349,  350,  495,  496  (Gr,  NY,  UC,  US);  alkaUne  meadows  near  Mexico  City, 
PringU  6892  (Gr,  NY,  UC,  US). 

SYNONYMS. 

1.  ATRIPLEX  POLTGAMA  Sesse,  in  Lagasca,  Gen.  Sp.  Nov.  12,  1816.  Apparently  the  long-leaved  form  of 
A.  linifolia.     Described  from  Mexican  specimens. 

2.  Obione  linifolia  Moquin,  Chenop.  Enum.  74,  1840.     Based  upon  Atriplex  linifolia. 

3.  0.  POLYGAMA  Moquin,  in  De  CandoUe,  Prodr.  13':  114,  1849.     Based  upon  Atriplex  polygama,  which  see. 


A.    LINIFOLIA — A.    FRUTICULOSA.  309 

RELATIONSHIPS. 

Although  sharply  set  off  from  all  of  its  allies,  this  species  clearly  stands  next  to  A. 
pentandra  muricata,  from  which  it  differs  especially  in  the  elongated  linear  entire  leaves, 
in  the  uniformly  well  developed  staminate  inflorescence,  and  in  the  marked  tendency 
towards  dioecism.  In  the  last  feature  linijolia  approaches  barclayana,  but  in  other 
respects,  and  especially  in  the  bracts,  these  two  are  very  unlike.  It  is  probable  that 
both  stand  near  the  phylogenetic  connection  between  the  group  of  monoecious  herba- 
ceous species  and  the  dioecious  shrubby  ones. 

ECOLOGY  AND  USES. 

Nothing  is  known  of  the  ecology  and  uses  of  this  Mexican  species. 
31.  ATRIPLEX  FRUTICULOSA  Jepson,  Pittonia  2:306,  1892.    Plate  48.    Ballscale. 

Spreading  or  nearly  erect  perennial  herb  from  a  woody  base  or  rarely  the  stems  also 
woody,  the  plant  then  suffruticose,  0.5  to  3  dm.  high,  the  stems  when  procumbent  a 
few  cm.  to  3  dm.  long;  branches  slender,  terete,  not  grooved  or  striate,  coarsely  furfura- 
ceous,  glabrate  and  then  stramineous  or  reddish,  the  bark  becoming  dark  and  fissured 
on  old  woody  stems;  leaves  all  alternate,  mostly  short-petioled,  the  upper  ones  sessile, 
narrowly  elliptic  or  linear-lanceolate,  acute  at  each  end,  0.5  to  1.5  cm.  long,  0.2  to  0.4 
cm.  wide,  entire,  moderately  thick  but  not  succulent,  gray  on  both  faces  with  a  dense 
permanent  scurf,  soft,  1 -nerved;  flowers  monoecious,  the  staminate  glomerules  in  short 
terminal  interrupted  spikes,  these  commonly  reduced  to  1  or  2  dense  globose  clusters 
at  the  end  of  each  branch  or  the  spike  rarely  up  to  6  cm.  long,  the  pistillate  flowers  mixing 
slightly  with  the  lower  staminate  and  continuing  down  the  stems  in  the  leaf -axils; 
perianth  apparently  always  5-cleft  in  the  staminate  flowers,  wanting  in  the  pistillate; 
fruiting  bracts  sessile  or  subsessile,  not  compressed  or  only  slightly  flattened,  united  to 
above  the  middle,  orbicular-obovate  or  subglobose,  3  to  4  mm.  long  and  nearly  as 
broad,  narrowly  margined  and  acutely  dentate  from  the  middle  upwards,  the  sides  neither 
strongly  nerved  nor  reticulated,  tooth-crested  or  muricate  or  sometimes  smooth  and 
then  with  a  suggestion  of  longitudinal  nerves,  indurate;  seed  1.4  to  1.7  mm.  long,  dark 
brown;  radicle  superior. 

Sacramento  and  San  Joaquin  Valleys,  Cahfornia.  Type  locaHty,  alkaline  soil  near 
Little  Oak,  Solano  County,  California.  Collections:  South  of  Willows,  Glenn  County, 
Hall  11003  (UC);  near  Norman,  Glenn  County,  May  26,  1898,  Davy  (UC);  type  collec- 
tion, August  16,  1892,  Jepson  (Herb.  Jepson,  herbaceous  to  the  base);  Wilson  Creek, 
near  Vacaville,  September  30,  1893,  Jepson  (Herb.  Jepson,  suffruticose,  the  woody  stems 
4  mm.  thick) ;  Livermore  Pass,  May,  1898,  Davy  (UC) ;  near  Crows  Landing,  Stanislaus 
County,  Hall  11016  (UC);  10  km.  south  of  Dos  Palos,  Fresno  County,  Hall  11022  (UC); 
5.5  km.  south  of  Mendota,  Fresno  County,  Hall  11762  (UC);  Laton,  Fresno  County, 
Kearney  25  (US). 

RELATIONSHIPS. 

This  and  A.  coulteri  are  very  closely  related,  as  will  be  explained  more  fully  under  the 
latter  species.  Taken  together  they  represent  a  branch  of  the  pentandra  line  which  has 
reached  farther  to  the  northwest  than  any  other,  except  perhaps  bradeosa.  They  differ 
from  other  western  members  of  the  group  in  the  notable  reduction  in  the  size  of  the 
leaves.  These  are  consistently  entire.  The  present  species  differs  from  bracteosa  also 
in  the  perennial  habit,  absence  of  a  pronounced  odor,  and  other  features. 

The  flower  and  fruit  characters  of  A.  fruticulosa  are  remarkably  constant,  as  also  are 
those  of  the  foliage.  On  the  other  hand,  the  habit  is  extremely  variable.  The  type 
collection  includes  plants  that  are  so  slender  and  erect  that  they  appear  to  be  annual 
and  others  in  which  the  herbaceous  stems  arise  from  a  short,  woody  base,  the  plant  in 


310  GENUS   ATRIPLEX. 

this  case  plainly  perennial  and  suffrutescent,  as  described  by  Jepson.  Other  collections 
include  plants  with  decidedly  woody  stems  up  to  4  mm.  in  diameter.  The  only  specimens 
of  this  extreme  woody  form  are  Jepson's  plants  from  Wilson  Creek,  Solano  County, 
September  30,  1893.  It  is  remarkable  that  all  recent  collections  are  of  plants  in  which 
the  leafy  stems  are  spreading  or  prostrate,  and  herbaceous  throughout  except  at  the 
very  base,  where  they  are  attached  to  a  more  or  less  woody  crown.  Although  normally 
a  perennial,  A.  fruticulosa  flowers  and  seeds  in  the  first  season,  at  least  under  garden 
conditions.    These  one-year-old  plants  are  herbaceous  throughout. 

ECOLOGY  AND  USES. 

A  triplex  fruticulosa  grows  more  or  less  copiously  in  alkaline  flats  of  the  Great  Valley 
of  Cahfornia,  usually  associated  with  Distichlis.  It  has  become  ruderal  to  some  extent, 
where  it  is  found  on  railway  embankments.  The  plants  flower  most  abundantly  in 
midsummer,  but  bloom  in  some  degree  from  March  to  November. 

This  species  is  much  relished  by  cattle  and  sheep,  and  is  kept  grazed  down  to  a  mat- 
like form,  but  it  is  not  large  enough  to  be  of  importance  as  a  rule. 

32.  ATRIPLEX  COULTERI  (Moquin)  Dietrich,  Syn.  PI.  5:537,  1852.     Plate  48. 

Spreading  perennial  herb,  1  to  3  dm.  high,  the  stems  sometimes  10  dm.  long,  branched 
from  the  base;  branches  slender,  terete,  not  grooved  or  striate,  sparsely  furfuraceous, 
glabrate,  stramineous  or  sometimes  reddish,  the  bark  pale  and  persistent  but  splitting 
near  the  base  of  the  stems;  leaves  all  alternate,  on  short  petioles  or  the  upper  ones 
sessile,  narrowly  elliptic,  narrowly  oblong  or  lanceolate,  tapering  at  base,  acute  at  apex, 
1  to  2  cm.  long,  0.2  to  0.4  cm.  wide,  entire,  rather  thin,  gray  with  a  close  fine  scurf  or 
slightly  greenish  above,  soft,  1 -nerved;  flowers  monoecious,  the  staminate  glomerules 
in  a  few  upper  axils  and  in  terminal  spikes  less  than  3  cm.  long,  the  pistillate  flowers 
in  small  clusters  in  the  upper  leaf-axils,  a  few  sometimes  in  the  lower  staminate  clusters; 
perianth  5-cleft  in  the  staminate  flowers,  wanting  in  the  pistillate;  fruiting  bracts  sessile 
or  subsessile,  moderately  compressed,  united  to  the  middle,  obovate  but  with  narrowed 
summit,  2.5  to  3  mm.  long  and  about  as  broad,  sharply  dentate  from  the  middle  upwards, 
the  sides  with  3  prominent  raised  longitudinal  nerves  or  these  obscure  (as  in  the  tjrpe 
specimen),  also  with  cross- veinlets  and  a  few  sharp  tubercles  or  the  tubercles  wanting 
(as  in  the  type);  seed  1.3  to  1.5  mm.  long,  brown;  radicle  superior.  {Obione  coulteri 
Moquin  in  DeCandoUe,  Prodr.  13^:113,  1849.) 

Coast  of  southern  California,  including  the  adjacent  islands,  probably  also  in  northern 
Lower  California.  Type  locality,  California.  Collections:  Type  collection,  Coulter 
(fragment  in  Herb.  Gray,  ex-herb.  Hooker);  Bixby,  Los  Angeles  County,  Brandegee 
(UC);  Gardena,  Los  Angeles  County,  Braunton  265  (US);  Catalina  Island,  Macbride 
and  Payson  870  (Gr);  Avalon,  Santa  Catalina  Island,  common  at  a  single  locality  at 
450  m.  altitude,  March,  1898,  Trask  (US);  Chino  Creek,  south  of  Ontario,  San  Ber- 
nardino County,  Johnston  1275  (UC);  Trabuco  Canon,  near  Capistrano,  Orange  Coimty, 
Abrams  3270  (DS,  Gr,  UC);  La  JoUa,  San  Diego  County,  Grant  (UC);  San  Diego, 
near  the  shore,  May,  1878,  Cleveland  (Gr). 

RELATIONSHIPS. 

This  species  is  very  closely  connected  with  A.  fruticulosa,  but  each  has  certain  features 
so  highly  specialized  that  both  are  retained  in  specific  rank.  One  belongs  to  the  coastal 
slope  of  southern  California,  the  other  to  the  interior  valleys  of  the  same  State.  Neither 
the  ranges  nor  the  characters  fully  meet.  The  present  species  exhibits  the  greater 
reduction  in  the  size  of  the  fruiting  bracts  and  seed  and  often  also  in  the  staminate 


A.    COULTERI — A.    DECUMBENS.  311 

inflorescence.  On  this  basis  it  might  be  taken  as  the  less  primitive,  but,  on  the  other 
hand,  the  bracts  are  almost  always  longitudinally  3-nerved  and  reticulate-veiny,  these 
features  indicating  a  connection  with  A.  pentandra  muricata,  which  represents  the  com- 
mon ancestral  stock.  The  texture  and  degree  of  compression  of  the  bracts  are  about 
the  same  in  coulteri  and  muricata,  while  in  fruticulosa  the  bracts  are  but  slightly  if  at 
all  compressed,  therefore  subgloboid,  and  firmly  indurated.  These  thick  and  hard 
fruiting  bracts  furnish  perhaps  the  best  means  of  distinguishing  fruticulosa  from  coulteri. 
Also,  the  strongly  veined  and  reticulate  bracts  of  the  latter  usually  serve  as  a  dis- 
tinguishing feature,  but  in  a  few  specimens,  such  as  the  types  themselves,  the  nerves 
and  reticulations  are  obscure. 

ECOLOGY  AND  USES. 
Atriplex  coulteri  is  similar  to  A.  fruticulosa  in  its  ecological  relations,  but  it  occurs 
on  the  coastal  slope  and  the  islands  of  southern  California.    It  has  no  known  uses,  apart 
from  incidental  grazing. 

33.  ATRIPLEX  DECUMBENS  Watson,  Proc.  Am.  Acad.  12:275,  1877.     Plate  49. 

Prostrate  perennial  herb,  slightly  woody  below,  the  stems  much  branched  through- 
out and  forming  tangled  mats  often  several  meters  across  and  3  to  4  dm.  deep;  branches 
tough  and  flexuous,  terete,  densely  white-scurfy  and  the  scurf  either  persistent  or 
deciduous,  the  stems  then  stramineous,  the  bark  smooth,  except  on  old  portions  near 
the  base;  leaves  very  numerous,  nearly  all  opposite,  sessile,  broadly  elliptic  to  ovate, 
narrowly  rounded  to  the  base,  acute  at  apex,  0.8  to  2  cm.  long,  0.4  to  1  cm.  wide  (rarely 
up  to  3.5  cm.  long  by  1.5  cm.  wide),  entire,  thick,  somewhat  succulent  when  fresh, 
white  on  both  sides  with  a  dense  permanent  scurf,  soft,  1-nerved;  flowers  dioecious, 
the  staminate  glomerules  in  naked  moniliform,  terminal  spikes  1  to  10  cm.  long,  the 
pistillate  ones  in  small  clusters  in  the  leaf-axils;  perianth  5-cleft  in  the  staminate  flowers, 
wanting  in  the  pistillate;  fruiting  bracts  sessile,  compressed,  united  to  the  middle, 
ovate  or  rhombic,  5  to  8  mm.  long,  5  to  6  mm.  broad,  with  broad  free  margins  above 
the  middle,  entire  or  erosely  denticulate,  the  sides  neither  appendaged  nor  nerved; 
seed  about  1  mm.  long,  light  brown;  radicle  superior.  Pericarp  continued  as  a  flat, 
broad  sheath  which  incloses  the  thickened  bases  of  the  stigmas. 

Proximity  of  the  Pacific  Ocean,  from  Santa  Barbara  County,  California,  to  San  Quentin 
Bay,  Lower  California,  including  the  adjacent  islands  (except  the  Santa  Cruz  Islands, 
where  the  species  is  not  known).  Type  locality,  near  San  Diego,  California.  Collections, 
all  from  southern  and  Lower  California:  Santa  Barbara,  near  the  beach,  September, 
1882,  Bingham  (Gr);  Long  Beach,  July,  1896,  McClatchie  (UC);  Newport  Bay,  Los 
Angeles  County,  1882,  Nevin  (Gr);  Santa  Catalina  Island  (Catalina  Cove),  Pendleton 
H27  (UC);  San  Clemente  Island,  Trask  32  (US);  San  Nicholas  Island,  April,  1897, 
Trask  (US) ;  La  JoUa,  San  Diego  County,  Clements  58  (UC) ;  type  collection,  near  San 
Diego,  1875,  Palmer  334  (Gr,  NY);  borders  of  the  bay  near  Old  Town,  San  Diego, 
Abrams  S454  (DS,  Gr,  NY,  UC,  US);  National  City,  San  Diego  County,  Hall  11214 
(UC);  San  Quentin  Bay,  Lower  California,  Palmer  740  (NY). 

SYNONYM. 

1.  Atriplex  watsoni  Nelson,  in  Abrams,  Fl.  Los  Angeles,  128,  April  5,  1904;  Proc.  Biol.  Soc.  Wash.  17:99, 
April  9,  1904.— This  name  is  in  accordance  with  the  American  Code.  According  to  the  International  Code, 
however,  the  name  A.  decumbens  Watson  is  available  for  this  species,  since  the  earher  A.  decumbens  Roemer 
and  Schultz  is  synonymous  with  the  still  older  A.  prostrata  R.  Brown,  an  Australian  species. 


312  GENUS   ATRIPLEX. 

RELATIONSHIPS. 

This  species  and  A.  matamorensis  constitute  a  small  natural  group,  the  relationships  of 
which  are  not  known.  It  seems  that  they  have  been  long  separated  from  the  more  prim- 
itive species  and  that  they  have  not  given  rise  to  the  more  modern  ones.  The  superior 
radicle,  together  with  the  dioecious  habit,  is  suggestive  of  a  starting-point  for  the  large 
group  of  dioecious  perennial  species,  but  there  is  no  direct  connection  with  any  of  these. 
Moreover,  the  dioecious  true  shrubs  can  be  more  logically  connected  with  the  monoecious 
herbs  through  the  pentandra-barclayana  line,  or  it  is  not  impossible  that  they  have  had 
an  origin  entirely  independent  of  any  of  the  present  North  American  species. 

A.  decumbens  and  A.  matamorensis  possess  certain  features  not  present  in  any  species 
that  they  resemble  in  other  characters.  The  opposite  leaves  are  noteworthy  in  this 
connection.  Especially  unique  is  the  dilation  of  the  pericarp  around  the  thickened 
bases  of  the  stigmas.  It  is  such  considerations  that  lead  to  the  assembling  of  these  two 
species  into  a  single  close  group,  notwithstanding  their  rather  wide  geographic  separation. 

Constancy  in  all  essential  characters  is  a  feature  of  A.  decumbens.  The  only  notable 
exception,  aside  from  the  usual  variation  in  the  size  of  the  fruiting  bracts,  is  the  presence 
of  rather  well-marked  forms  differing  in  the  size  of  the  leaf.  The  type  specimen  is  from 
an  average  robust  plant,  the  largest  leaves  measuring  1.5  cm.  long  by  1  cm.  wide.  In  an 
extremely  large-leaved  form  the  leaves  measure  3.5  cm.  long  by  1.4  cm.  wide  and  in  this 
the  staminate  inflorescence  also  reaches  the  maximum  length  of  10  cm.  (Santa  Barbara, 
Bingham,  Gr).  The  opposite  extreme  is  a  form  with  crowded  subimbricate  leaves  only 
0.8  to  1.2  cm.  long  by  0.3  to  0.6  cm.  wide.  This  comes  from  San  Clemente  Island  (August 
25,  1894,  Brandegee,  UC)  and  from  the  mainland  at  National  City  {Hall  11214,  UC). 
Since  these  various  forms  can  not  be  correlated  with  geographic  distribution,  and  since 
there  is  evidence  of  partial  intergradation,  it  is  believed  that  they  are  ecads. 
ECOLOGY  AND  USES. 

Atriplex  decumbens  regularly  forms  dense  mats  one  to  several  feet  in  diameter,  from 
the  back-strand,  where  it  grows  with  Distichlis  and  Oenothera  bistorta,  to  the  adjacent 
slopes  of  Stipa  setigera  and  Avena  fatua,  where  also  occur  A.  semibaccata,  Baeria  chryso- 
stoma,  Layia  platyglossa,  Eschscholtzia,  Platystemon,  etc.  It  is  distinctly  halophytic, 
but  less  so  than  A.  leucophylla.     The  plants  bloom  from  April  to  July  or  later. 

This  species  is  grazed  to  a  slight  extent  by  cattle,  though  they  find  the  associated  A. 
semibaccata  much  more  succulent. 

34.  ATRIPLEX  MATAMORENSIS  Nelson,  Proc.  Riol.  Sec.  Wash.  17:99,  1904.     Plate  49. 

Erect  or  ascending  perennial,  woody  toward  the  base,  2  to  4  dm.  high;  branches 
rather  slender,  terete  but  irregular  and  often  crooked,  obscurely  furfuraceous,  the  old 
bark  breaking  apart  and  exfoliating ;  leaves  nearly  all  strictly  opposite,  sessile,  lanceolate 
from  a  broad  base,  crowded  and  often  imbricate,  obtuse  at  base,  acute  at  apex,  0.2  to 
0.5  cm.  long,  0.1  to  0.3  cm.  wide,  entire,  thick,  gray  with  a  dense  scurf,  soft,  l-nerved; 
flowers  dioecious,  the  staminate  not  known,  the  pistillate  solitary  or  several  in  axillary 
glomerules,  these  in  rigid  leafy  spikes;  perianth  wanting  in  the  pistillate  flowers;  fruiting 
bracts  sessile,  strongly  compressed,  united  to  the  middle  or  above,  nearly  orbicular,  obtuse 
but  sometimes  with  a  short  mucronate  apex,  2.5  to  3  mm.  long  and  wide,  sharply  and 
evenly  dentate  nearly  to  the  base,  the  sides  not  appendaged  but  strongly  1-  or  3-nerved; 
seed  1.2  mm.  long,  yellowish;  radicle  superior.  Pericarp  continued  as  a  flat  white 
sheath  around  the  bases  of  the  stigmas. 

Southwestern  Texas  and  Tamaulipas.  Type  locality,  Rio  Grande  Valley,  near  Mata- 
moras,  Tamaulipas.  Collections :  Type  collection,  Matamoras  to  San  Fernando,  October, 
1830,  Berlandier  3201  (Gr,  NY);  Corpus  Christi  Bay,  southwestern  Texas,  Palmer  1160 
(Gr,  US);  vicinity  of  Corpus  Christi,  Texas,  Rose  18086  (US). 


A.    MATAMORENSIS — A.    BARCLAYANA.  313 

SYNONYM. 

1.  Atriplex  oppositifolia  Watson,  Proc.  Am.  Acad.  9:118,  1874.  The  original  name  for  A.  matamor- 
ensis,  but  antedated  by  A.  oppositifolia  Vilmorin,  a  European  species  which  apparently  still  has  taxonomic 
standing. 

RELATIONSHIPS. 

The  relationships  of  A.  matamorensis  have  been  considered  under  A.  decumbens.  In 
addition  to  what  is  there  said,  attention  should  be  called  to  the  close  similarity  between 
the  fruiting  bracts  of  matamorensis  and  elegans,  these  organs  being  strongly  compressed, 
nearly  orbicular,  and  evenly  dentate  in  both.  The  habit  and  foliage  of  the  present  species 
is  more  like  that  of  A.  julacea  than  any  other.  It  is  doubtful,  however,  if  either  of  these 
similarities  indicate  anything  more  than  a  parallel  development  in  species  widely  sepa- 
rated phylogenetically.  As  contrasted  with  decumbens,  matamorensis  is  a  more  woody 
plant  with  greatly  reduced  foliage  and  with  more  nearly  orbicular,  closely  dentate  fruiting 
bracts. 

ECOLOGY  AND  USES. 

Nothing  is  known  of  the  ecology  and  uses  of  this  Mexican  species. 

35.  ATRIPLEX  BARCLAYANA  (Bentham)  Dietrich,  Syn.  PI.  5:537,  1852.    Plate  49. 

Erect  or  prostrate  perennial  shrub  or  herb,  usually  woody  at  least  toward  the  base, 
2  to  15  dm.  high;  branches  stout,  terete  or  rarely  somewhat  angled,  sometimes  striate 
after  the  fall  of  the  scurf,  densely  white-furfuraceous  or  glabrate  and  reddish,  the  bark 
fissured  on  old  plants ;  leaves  alternate,  except  perhaps  the  lower,  short-petioled  or  nearly 
sessile,  obovate  or  broadly  elUptic,  tapering  to  the  base,  obtuse  or  mucronate  at  apex,  1 
to  4  cm.  long,  0.5  to  2  cm.  wide,  entire  or  undulate  or  dentate  in  one  subspecies  (lurida), 
thick,  white  with  a  dense  scurf  (the  leaves  thinner,  less  scurfy,  and  greenish  in  some 
specimens,  particularly  in  minor  variation  1) ;  flowers  dioecious,  the  staminate  in  glomer- 
ules  scattered  along  the  branches  of  a  short  spreading  terminal  panicle,  the  pistillate  in 
small  axillary  glomerules  of  a  narrow  leafy-bracted  terminal  panicle,  this  0.5  to  2  dm.  long; 
perianth  5-cleft  in  the  staminate  flowers,  wanting  in  the  pistillate;  fruiting  bracts  sessile 
or  short-stalked,  compressed  and  obovate  or  suborbicular  to  thickened  and  globoid,  nar- 
rowed at  base,  united  at  least  halfway  up,  usually  only  the  margins  distinct,  the  tip  obtuse 
and  dentate  or  ovate-acute  or  subulate,  the  whole  bract  2  to  4  mm.  long  (occasional  pre- 
cocious bracts  up  to  7  mm.  long),  2  to  5  or  8  mm.  wide,  with  a  few  small  teeth  near 
the  apex  or  dentate  also  down  the  margins,  the  sides  either  tuberculate  or  cristate  or 
unappendaged,  often  irregularly  thickened;  seed  about  1  to  1.5  mm.  long,  brown;  radicle 
superior.     (Obione  barclayana  Bentham,  Botany  Voyage  Sulph.  48,  1844.) 

Northwestern  Mexico,  from  the  coast  of  Sinaloa  and  Sonora  across  Lower  California. 

SUBSPECIES. 

Eight  species  have  been  described  from  what  is  here  included  under  A .  barclayana.  One 
is  based  upon  leaf  characters,  the  others  upon  the  nature  of  the  bracts  and  supported  in 
some  cases  by  quite  unimportant  features  of  habit  or  of  the  scurf.  After  assembling  all 
of  the  available  material,  including  a  very  fine  series  of  specimens  recently  collected  by 
Mr.  I.  M.  Johnston  on  the  California  Academy  of  Sciences  Expedition  to  the  Gulf  of 
California,  it  seems  doubtful  if  any  of  these,  with  possibly  the  exception  of  A.  lurida, 
can  be  advantageously  retained  even  as  subspecies.  Much  individual  variation  is  appar- 
ent and  single  plants  very  frequently  have  fruiting  bracts  of  two  or  more  of  the  "species." 
However,  the  differences  between  the  extremes  are  so  striking  that  it  seems  desirable  to 
give  some  kind  of  taxonomic  recognition  to  the  more  frequently  recurring  forms.  For 
this  reason  all  of  the  variations  have  been  assembled  into  the  following  6  subspecies. 


314 


GENUS   ATRIPLEX. 


Fig.  43. — Phylogenetic  chart  of  the  ehrubby  dioeciouB  Bpeciee  of  Alriplex. 


A.    BARCLAYANA.  315 

Key  to  the  Subspecies  of  Atriplex  bardayana. 

Bracts  compressed  (sometimes  appearing  thickened  by  the  tubercles  when  these  are  present), 
mostly  as  wide  as  long  or  wider  except  in  magdalenae. 
Leaves  entire. 

Bracts  dentate  from  summit  to  middle  or  lower. 

Length  and  width  of  bracts  about  equal (a)  palmeri  (p.  315). 

Length  of  bracts  much  exceeded  by  their  width (6)  dilatata  (p.  315). 

Bracts  3-toothed  at  summit,  sides  entire (c)    magdalenae  (p.  315). 

Leaves  saliently  dentate (d)  lurida  (p.  315). 

Bracts  much  thickened,  convex  on  the  sides,  mostly  longer  than  wide. 

Bracts  laciniate  around  summit  and  well  down  the  sides,  the  margin  foliaceous  above,   (e)   sonorae  (p.  316). 
Bracts  entire  except  at  summit,  where  there  are  only  a  few  small  teeth,  the  margin  not 

fohaceous (J)   typica  (p.  316). 

35a.  Atriplex  barclayana  palmeri  (Watson). — Leaves  entire;  fruiting  bracts  com- 
pressed, sometimes  appearing  thickish  when  tubercled,  cuneate-orbicular  or  cuneate- 
obovate,  about  3  mm.  long,  as  wide  or  slightly  wider;  margins  wing-like,  coarsely  lacini- 
ate-dentate  nearly  to  the  base  of  the  bract;  faces  smooth  or  tuberculate.  {A.  palmeri 
Watson,  Proc.  Am.  Acad.  1 1 :  146,  1876.)  Islands  off  the  west  coast  of  Lower  California; 
also  on  islands  in  the  Gulf  of  California.  Type  locality,  Guadalupe  Island.  Collections: 
San  Luis  Island,  Johnston  3320  (SF,  minor  variation  3,  A.  insularis  Rose);  Santa  Inez 
Island,  Johnston  3653  (SF,  same  variation);  Raza  Island,  Palmer  155  (Gr,  SF,  US); 
same  locality,  Palmer  158  and  159  (US,  the  former  the  tjrpe  of  A.  insularis  Rose,  minor 
variation  3);  Raza  Island,  growing  among  rocks,  facing  the  lagoon,  Johnston  3210  (SF, 
with  ascending  herbaceous  branches,  5  dm.  high,  minor  variation  3,  A.  insularis  Rose, 
but  some  bracts  smooth) ;  same  spot,  Johnston  3211  (SF,  shrubby,  1  meter  high,  staminate 
plant,  a  few  mostly  smooth  bracts  in  the  leaf-axils) ;  Raza  Island,  on  silty  flat  at  southwest 
end,  Johnston  3214  (SF,  nearly  prostrate,  stems  woody,  same  variation  in  bracts  as  No. 
3210);  same  but  on  south  side,  Johnston  3213  (SF,  with  loosely  ascending  stems  3  to  5 
dm.  high,  same  variation  in  bracts  as  No.  3210);  San  Benito  Island,  March  27,  1897, 
Brandegee  (UC) ;  Magdalena  Island,  Orcutt  6  (US) ;  type  collection,  1875,  Palmer  83  (Or) ; 
Guadalupe  Island,  Palmer  862  (Gr,  US)  and  863  (Gr),  also  April  3,  1889  (UC);  Guada- 
lupe Island,  April  24,  1885,  Greene  (UC,  US) ;  Guadalupe  Island,  March  20,  1897,  Bran- 
degee (UC,  plants  mainly  staminate,  but  with  a  few  bracts  in  the  leaf-axils) ;  Seal  Island, 
Rose  16818  (NY,  US,  minor  variation  3,  A.  insularis  Rose). 

356.  Atriplex  barclayana  dilatata  (Greene). — Leaves  entire  or  slightly  sinuate 
or  inclined  to  be  dentate;  fruiting  bracts  compressed,  or  somewhat  thickened  when 
strongly  tuberculate,  wider  than  long,  3  to  6  mm.  long,  5  to  8  mm.  wide;  margins  wing- 
like, thin,  irregularly  laciniate-dentate  nearly  to  the  base  of  the  bracts;  faces  either 
smooth  or  low-tuberculate  or  conspicuously  crested  (in  minor  variation  4,  A.  rosei 
Standley).  {A.  dilatata  Greene,  Pittonia  1:264,  1889.)  Guadalupe  and  San  Benito 
Islands,  off  the  west  coast  of  Lower  California.  Type  locality,  San  Benito  Island. 
Collections:  Guadalupe  Island,  Rose  16022  (US,  type  of  A.  rosei  Standley,  minor  varia- 
tion 4);  San  Benito  Island,  Pabiier  907  (US);  San  Benito  Island,  Anthony  269  (Gr, 
DS,  NY,  UC,  US);  San  Benito  Island,  Rose  16074  (NY,  US). 

35c.  A.  BARCLAYANA  MAGDALENAE  (Brandegee). — Leaves  entire;  fruiting  bracts  mod- 
erately compressed,  cuneate-obovate,  about  4  to  4.5  mm.  long,  3.5  to  4  mm.  wide;  margins 
developed  only  around  the  summit,  there  deltoid  and  tridentate;  faces  smooth.  (A. 
magdalenae  Brandegee,  Proc.  Calif.  Acad.  II,  2:200,  1889.)  Magdalena  Island,  off  the 
west  coast  of  Lower  California.  Type  locality,  Magdalena  Island.  Collection:  Type 
collection,  February  20,   1889,  Brandegee  (UC). 

35d.  Atriplex  barclayana  lurida  (Brandegee). — Leaves  (rather  thin)  acutely 
dentate  with  broad  salient  teeth  or  some  only  crenate,  the  upper  mostly  entire ;  fruiting 
bracts  compressed,  cuneate-orbicular,  2  to  3  mm.  long,  2  to  4  mm.  wide;  margins  wing- 


316  GENUS   ATRIPLEX. 

like  around  the  summit,  deeply  and  acutely  dentate  to  midway  of  the  bract;  faces 
smooth.  {A.  lurida  Brandegee,  1.  c.)  Mainland  of  Lower  California.  Type  locality, 
San  Gregorio.  Collections:  Sandy  plains  near  Santa  Gertrudis  Island,  Pur  pus  2  (DS, 
UC) ;  25  miles  north  of  San  Ignacio,  Nelson  7206  (US) ;  tj-pe,  February  2,  1889,  Brandegee 
(UC);  Agua  Verde,  Rose  16575  (US,  staminate  only);  Los  Dolores,  1892,  Bryant  (UC). 

35e.  Atriplex  barclayana  sonorae  (Standley). — Leaves  entire;  fruiting  bracts 
moderately  thick  and  spongious,  the  body  convex  on  the  sides  and  commonly  spindle- 
shaped  (including  the  narrowed  pedicel-like  base),  the  whole  bract  3  to  4  mm.  long,  2.8 
to  4  mm.  wide,  usually  a  trifle  longer  than  wide;  margins  flat,  herbaceous,  laciniate  from 
apex  to  halfway  down  the  sides  of  the  bract ;  faces  with  2  or  more  sharp  spine-like  pro- 
cesses similar  to  the  teeth  of  the  margins.  {A.  sonorae  Standley,  N.  Am.  Fl.  21:62, 
1916.)  Coast  of  Sonora  and  Sinaloa,  islands  in  the  Gulf  of  California,  Cape  Region  of 
Lower  California,  and  Magdalena  Island.  Type  locality,  in  alkaline  soil  near  Empalme, 
Sonora.  Collections:  Type  collection,  Sonora,  Rose,  Standley  and  Russell  12631  (US); 
Guaymas,  Sonora,  Palmer  670  and  690  (US) ;  same  locality,  Pahner  671  and  672  (US, 
minor  variation  1);  San  Luis  Gonzales  Bay,  Lower  California,  Johnston  3351  (SF); 
Gulf  of  California:  Angel  de  la  Guarda  Island,  Johnston  4234  (SF);  North  San  Lorenzo 
Island,  Johnston  4196  (SF) ;  San  Esteban  Island,  Johnston  3189,  3191  (SF,  UC,  with  some 
bracts  as  in  subspecies  typica) ;  same  locality,  Johnston  3192  (SF,  UC,  all  bracts  of  sub- 
species sonorae) ;  Santa  Inez  Island,  Johnston  3651  (SF) ;  Altata,  vicinity  of  Culiacan, 
Sinaloa,  September  2, 1904,  Brandegee  (Gr,  UC) ;  Lower  California:  Espiritu  Santo  Island, 
1892,  Bryant  (UC) ;  San  Jose  del  Cabo,  Anthony  358  (DS,  UC,  US,  intermediate  to  sub- 
species typica);  Magdalena  Island,  February  26,  1889,  Brandegee  (UC). 

35/.  Atriplex  barclayana  typica. — Leaves  entire;  fruiting  bracts  thick  and  spon- 
gious, the  body  globoid,  2.5  to  4  or  rarely  5  mm.  long,  2.5  to  4  mm.  wide;  margins  entire, 
except  at  the  summit,  where  usually  there  are  a  few  short  teeth;  faces  irregularly  swollen, 
often  with  a  vertical  furrow  on  each  side  of  the  enlarged  midrib,  nearly  smooth,  or  with  a 
few  minute  obtuse  tubercles.  {Obio7ie  barclayana  Bentham,  Botany  Voyage  Sulph.  48, 
1844.)  Seacoast  of  Sonora,  Sinaloa,  and  Lower  California  and  on  the  adjacent  islands. 
Type  locahty,  Magdalena  Bay,  Lower  California.  Collections:  Tepoca  Bay,  Sonora, 
Johnston  3284  (SF,  UC) ;  island  in  harbor  of  Guaymas,  Sonora,  Rose  12564  (NY,  US) ; 
Gulf  of  California:  Angel  de  la  Guarda  Island,  Rose  16766  (NY,  US);  San  Luis  Island, 
Johnston  3319,  3321  (SF) ;  Patos  Island,  Johnston  3242  (SF,  UC,  minor  variation  2); 
Tiburon  Island  (north  end),  Johnston  3259  (SF);  Tiburon  Island  (south  end).  Rose  16806 
(US) ;  Ildefonso  Island,  Johnston  3750,  3751,  and  3752  (SF);  Carmen  Island,  Palmer  874 
(Gr,  US) ;  Isla  Partida,  Johnston  3228  (SF,  UC,  some  undeveloped  bracts  resembUng 
those  of  subspecies  palmeri) ;  same  locality  and  collector,  3229  (SF,  UC,  typical) ;  Sal  si 
Puedes  Island,  Johnston  3525  (SF) ;  South  San  Lorenzo  Island,  Johnston  4191  (SF) ; 
Lower  California:  Los  Angeles  Bay,  Johnston  3429  (SF);  San  Francisquito  Bay,  Rose 
16753  (NY,  US);  Santa  Aqueda,  Palmer  259  (US);  Pichilinque  Island,  Rose  16519  (US); 
Santa  Maria  Bay,  Rose  16255  (NY,  US);  Lagoon  Head,  Palmer  809  (Gr,  NY,  US); 
Cedros  Island,  Palmer  754  (Gr,  NY,  US) ;  Ascension  Island,  August  17,  1897,  Bran- 
degee (UC);  Magdalena  Island,  Rose  16318  (NY,  US);  Altata,  Sinaloa,  Rose  1362  (US). 

MINOR  VARIATIONS  AND  SYNONYMS.' 

1.  Atriplex  barclayana  sonorae,  but  with  thin,  greenish  leaves  of  an  oblanceolate  shape,  many  of  them 
slenderly  cuspidate  at  apex.  Represented  by  Palmer  671,  672,  and  a  part  of  677,  all  at  the  United  States 
National  Herbarium,  and  collected  at  Guaymas,  where  grows  also  the  usual  form  of  sonorae.  The  plants  are 
apparently  more  herbaceous  than  the  usual  type,  in  which  the  leaves  are  thicker  and  broader,  obtuse,  and 

'Additional  synonymy  is  given  in  connection  with  the  description  of  each  of  the  subspecies. 


A.    BARCLAYANA.  317 

white-scaly,  but  the  bract  characters  assign  the  plants  cited  to  this  subspecies.  Among  the  collections  listed 
above  as  typica  and  sonorae  are  some  with  leaves  that  are  narrow  and  elliptic,  but  still  white  or  gray  with  a 
dense  scurf. 

2.  Atriplex  BARCLAYANA  TTPiCA,  but  With  dense  subcylindric  and  pyramidal  panicles  20  to  30  cm.  long  by 
8  to  10  cm.  broad,  heavy  with  fruiting  bracts.  This  form  is  from  a  protected  draw  on  Patos  Island,  Johnston 
S24^.  It  is  not  even  approached  in  density  and  size  of  the  inflorescence  by  any  of  the  other  numerous  col- 
lections. 

3.  A.  iNSULARis  Rose,  Contr.  U.  S.  Nat.  Herb.  1:  80,  1890. — The  form  or  state  of  A.  barclayana  palmeri  in 
which  the  bracts  are  appendaged  by  two  conspicuous  toothed  crests.  The  type  is  from  Raza  Island,  in  the  Gulf 
of  California.  Since  this  character  is  unreliable  in  other  species,  it  is  not  surprising  to  find  that  in  nearly  all  of 
the  collections  in  which  most  of  the  bracts  are  conspicuously  crested  there  are  some  (on  the  same  plant)  with 
smooth  sides.  A  number  of  such  are  cited  under  subspecies  palmeri.  An  attempt  was  made  in  the  North 
American  Flora  to  use  also  the  more  fruticose  branches  and  the  more  nearly  sessile  leaves  as  criteria  for  the 
separation  of  insularis.  But  the  type  specimens  indicate  that  palmeri  is  perhaps  as  woody  as  insularis  and  the 
original  descriptions  ("shrubby  at  base"  for  the  former,  "woody  below"  for  the  latter)  furnish  no  support  for 
the  distinction.  Mr.  Johnston,  who  collected  abundantly  on  Raza  Island,  considered  the  plants  as  all  closely 
similar  in  this  respect,  that  is,  all  had  a  woody  base  and  more  or  less  herbaceous,  ascending  or  decumbent 
branches.  His  plants  are  all  of  the  irisularis  form  as  to  most  of  the  bracts,  except  No.  3211,  which  is  a  staminate 
plant  with  well-developed  fruiting  bracts  in  the  leaf  axils.  These  bracts  arc  mostly  smooth  as  in  typical  palmeri, 
yet  tliis  was  one  of  the  most  woody  plants  found.  Other  plants  referred  to  insularis  on  the  characters  of  the 
bracts,  such  as  Palmer's  862,  are  less  than  3  dm.  high  and  herbaceous  nearly  to  the  base.  The  length  of  petiole 
is  equally  unsatisfactory.  On  the  type  sheet  of  insularis  some  petioles  are  one-third  the  length  of  the  blade, 
exactly  the  proportion  stated  for  pabneri,  and  the  large  series  of  specimens  now  at  hand  shows  conclusively  that 
this  feature  is  extremely  variable,  and  that  the  variations  do  not  parallel  those  of  other  characters.  Therefore, 
if  insularis  is  to  be  retained  in  any  rank,  it  must  be  on  the  single  character  of  the  appendages,  and  even  these  are 
absent  from  some  of  the  bracts. 

4.  A.  ROSEi  Standley,  N.  Am.  Fl.  21:60,  1916. — The  extreme  form  of  A.  barclayana  dilaiata  in  which  the 
bracts  are  6  to  8  mm.  •v,-\Aq  and  with  conspicuous  crests  on  the  face,  the  seeds  correspondingly  large.  The  type 
collection  from  Gaudalupe  Island  includes  a  splendid  series  of  bracts,  some  of  which  are  nearly  twice  as  wide  as 
long.  Others  of  the  same  collection  are  much  narrower,  and  some,  perhaps  immature,  are  scarcely  wider  than 
long.  For  the  most  part,  they  are  much  thicker  than  in  other  collections  of  subspecies  dilaiata  and  palmeri, 
some  apparently  not  at  all  compressed,  but  this  is  due  to  the  exceptional  development  of  the  tubercles  with 
thickened  bases,  as  indicated  by  other  bracts,  also  of  the  type  specimen,  which  are  strongly  compressed  and 
with  only  a  few  minute  appendages  on  the  face.     Some  of  the  leaves  are  slightly  sinuate  or  subdentate. 

RELATIONSHIPS. 

This  species  stands  near  the  beginning  of  that  great  phylogenetic  branch  of  Atriplexes 
characterized  by  a  shrubby  habit  and  dioecism.  The  evidence  for  this  is  found  in  the 
only  half-shrubby  nature  of  many  of  the  plants  and  in  the  almost  constant  occurrence  of 
at  least  a  few  pistillate  flowers  on  the  staminate  plants.  These  female  flowers  are  usu- 
ally well  formed  and  are  protected  by  normal  bracts  which  grow  in  clusters  from  the  upper 
leaf-axils,  that  is,  just  below  the  long  and  dense  staminate  inflorescence.  In  a  few  cases 
no  trace  of  fruiting  bracts  can  be  found,  indicating  that  a  complete  separation  has  been 
effected  in  these  individuals. 

In  assembling  the  numerous  variations  of  A.  barclayana,  it  is  found  that  these  fall  into 
two  groups,  which  may  be  conveniently  referred  to  as  the  'palmeri  and  the  typica  groups. 
These  differ  only  in  their  fruiting  bracts.  In  the  former,  the  bracts  are  distinctly  com- 
pressed, so  that  the  body  is  more  or  less  strongly  flattened,  that  is,  they  are  as  in  most 
Atriplexes  only  slight  modifications  from  the  reduced  foliage  leaf.  These  compressed 
bracts  are  sometimes  thickened  by  the  enlarged  bases  of  the  appendages,  or  tubercles, 
but  this  is  not  to  be  confused  with  the  swelling  or  thickening  of  the  body  proper.  The 
bracts  of  the  typica  group  are  distinctly  thickened  and  spongious,  so  that  the  body  is 
strongly  convex  on  each  face,  that  is,  approaching  globose.  The  bracts  of  the  palmeri 
group  are  usually  wider  in  proportion  to  their  length  than  are  those  of  the  typica  group. 
In  each  the  length  and  width  are  sometimes  equal,  and  the  subspecies  magdalenae  is  an 
exception,  but  in  the  main  the  tendencies  are  as  indicated.     It  seems  that  the  loss  of 


318 


GENUS   ATRIPLEX. 


tissue  which  goes  to  make  up  thickness  in  the  one  case  is  compensated  by  the  greater 
lateral  extension  in  the  other.  An  earnest  endeavor  has  been  made  to  utilize  these  bract 
features  as  criteria  for  the  retention  of  each  group  in  specific  rank,  but  the  too  frequent 
meeting  of  the  characters,  and  the  apparently  total  absence  of  correlated  features  seem 
to  make  this  impossible.  Furthermore,  there  are  some  collections,  such  as  Johnston's 
3228  from  Isla  Partida,  in  which  both  compressed  and  thickened  bracts  occur  on  the 


Fio.  44. — Phylogenetic  chart  of  the  subspecies  of  Alriplez  barclauana. 


same  plant.  This  is  possibly  a  case  of  hybridization,  but,  if  so,  the  wide  distribution  of 
both  types  over  the  same  area  could  be  expected  to  result  in  such  frequent  crossing  as  to 
swamp  the  specific  characters.  As  a  final  reason  for  merging  the  two  groups  may  be 
cited  a  parallel  pair  of  forms  under  A.  polycarpa,  one  with  compressed,  the  other  with 
thickened  bracts;  yet  here  these  characters  are  not  concomitant  with  any  others,  nor  can 
the  forms  be  assigned  to  different  geographic  areas. 

In  considering  these  two  groups  of  subspecies  from  an  evolutionary  viewpoint  it  seems 
that  the  palmeri  group  is  the  more  primitive.     This  is  because  the  bracts  are  more  like 


A.    BAECLAYANA.  319 

those  common  in  the  genus  and  less  highly  modified  from  the  original  leaf-like  structure. 
The  thickening  of  the  bracts  in  typica  has  resulted  in  the  almost  complete  loss  of  the  thin, 
herbaceous  borders.  From  these  considerations  it  becomes  necessary  to  place  the  pal- 
meri  group  first  in  a  phylogenetic  arrangement,  reserving  the  highly  specialized  taxonomic 
type  of  the  species,  that  is,  subspecies  typica,  for  treatment  at  the  end. 

The  subspecies  palmeri  exhibits  no  features  indicative  of  a  special  development.  On 
the  other  hand,  the  remarkable  width  of  the  compressed  bracts,  mentioned  above  as 
one  of  the  characters  of  the  palmeri  branch  of  the  species  finds  its  greatest  development  in 
subspecies  dilatata  (especially  the  minor  variation  called  A.  rosei  Standley).  Although 
the  shape  fluctuates  to  such  a  degree  that  future  studies  may  indicate  the  impracticabil- 
ity of  the  distinction,  it  seems  helpful  at  present  to  retain  a  subspecies  dilatata  for  this 
form.  Possibly  other  substantiating  characters  will  be  found  after  the  forms  have 
received  a  more  thorough  field  study.  As  far  as  now  known,  dilatata  is  confined  to  two 
islands  off  the  west  coast  of  Lower  California  (where  true  palmeri  also  grows),  but  one 
collection  from  Raza  Island,  in  the  Gulf  of  California,  has  bracts  up  to  5  mm.  wide  and  is 
therefore  to  be  classified  as  very  close  if  not  the  same  as  dilatata  {Johnston  32S2,  SF, 
UC),  and  other  collections  from  Raza  Island  {Palmer  155  and  156),  here  cited  as  sub- 
species palmeri,  were  identified  by  Rose  (Contr.  U.  S.  Nat.  Herb.  1 :80,  1890)  as  dilatata. 

The  subspecies  magdalenae  is  here  maintained  only  because  no  direct  intergradation 
with  palmeri  is  known,  although  the  two  come  from  the  same  island.  The  herbaceous, 
prostrate  habit  and  the  less  strongly  compressed  nature  of  the  bracts  will  furnish  char- 
acters substantiating  those  used  in  the  key,  if  the  former  are  found  to  be  constant,  which 
seems  unlikely.  Since  the  bracts  are  longer  than  broad  and  only  lightly  compressed,  this 
subspecies  should  perhaps  stand  ahead  of  palmeri,  connecting  this  with  typical  barclay- 
ana.  Its  rare  occurrence,  however,  and  this  only  on  an  outlying  island,  is  evidence  that 
it  is  a  divergent  type  that  did  not  give  rise  to  the  other  forms. 

The  most  easily  distinguished  subspecies  and  the  one  least  subject  to  intergradation 
is  lurida.  This  is  the  only  one  thus  far  found  to  be  generally  distributed  on  the  mainland 
of  Lower  California,  exclusive  of  the  Cape  Region  the  flora  of  which  is  more  like  that  of 
the  southern  islands.  It  has  not  been  collected  on  any  of  the  islands.  Two  collections 
of  typica  have  been  made  on  the  west  coast,  opposite  Cedros  Island.  Aside  from  this, 
the  other  subspecies  occur  only  in  Sonora  and  Sinaloa  and  on  the  islands  off  both  sides 
of  the  peninsula.  In  some  cases  a  single  subspecies  is  known  both  from  the  gulf  and  from 
islands  off  the  west  coast,  yet  none  of  them  are  known  to  mingle  with  lurida.  The  near- 
est approach  is  at  Agua  Verde  and  Los  Dolores,  where  lurida  grows  on  the  mainland  and 
other  subspecies  on  the  adjacent  islands.  Further  field  studies  and  also  experiments 
are  needed  to  determine  whether  lurida  is  an  ecologic  response  to  the  mainland  environ- 
ment or  an  hereditary  type  held  true  by  isolation. 

The  typica  branch  has  produced  but  two  subspecies,  typica  itself  and  sonorae.  This 
latter  is  characterized  by  having  the  margin  of  the  bract  more  fully  developed  around  the 
summit,  where  it  is  deeply  cut  into  a  number  of  sharp  teeth.  This  commonly  leaves  the 
lower  portion  as  a  spindle-shaped  structure,  the  base  of  which  is  pedicel-like.  In  the 
original  diagnosis,  Standley  differentiated  this  form  also  on  the  failure  of  the  bracts  to 
unite  above  the  middle.  However,  this  lack  of  union  applies  in  most  cases  only  to  the 
marginal  wings  and  therefore  may  be  looked  upon  as  another  expression  of  a  single  char- 
acter. A  careful  examination  of  the  much  more  copious  material  now  at  hand  indicates 
that  the  extent  of  fusion  varies  too  greatly  in  both  subspecies  to  be  of  taxonomic  value. 
After  all  of  the  available  material  has  been  classified  into  typica  and  sonorae  on  the  basis 
of  the  bracts,  it  is  found  that,  while  they  have  the  same  general  area  of  distribution,  they 
seldom  occur  at  the  same  station.  This  is  indicated  by  the  above  citation  of  collections. 
The  distribution  indicates  that  they  may  be  genetic  types  preserved  in  their  charac- 


320  GENUS  ATRIPLEX. 

ters  by  isolation.  Much  more  intensive  field  studies  will  be  necessary  before  this  can 
be  determined.  In  this  connection  it  must  be  pointed  out  that,  although  each  plant  usu- 
ally can  be  placed  in  one  or  the  other  of  the  subspecies,  this  is  done  by  ignoring  a  small 
number  of  bracts  which  may  come  closer  in  characters  to  those  of  the  other  form.  Some- 
thing of  the  variation  found  on  single  plants  is  indicated  in  plate  49.  When  bracts  of 
the  sonorae  type  occur  on  plants  with  typical  bardayana  bracts,  the  latter  fall  off  much 
more  easily  in  the  press,  indicating  an  earlier  maturity. 

ECOLOGY  AND  USES. 
Atriplex  bardayana  grows  commonly  in  the  sandy  or  gravelly  soil  of  back-strands 
and  of  alluvial  fans  at  the  mouths  of  canons,  as  well  as  on  dunes.  It  also  grows  inland 
in  gravelly  washes,  always  preferring  soil  that  is  slightlj'  or  not  at  all  saline.  In  all  such 
situations  it  occurs  as  a  scattered  secondary  species.  However,  on  the  guano  islands  of 
the  Gulf  of  California,  where  the  soil  is  discolored  with  guano  salts,  it  is  a  dominant, 
usually  associated  with  Amarantits  watsoni,  which  is  equally  important.  These  two 
species  constitute  the  initial  associes,  which  forms  95  per  cent  of  the  vegetation  of  such 
islets.     Nothing  is  known  of  the  uses  of  this  species. 

36.  ATRIPLEX  ACANTHOCARPA  (Torrey)  Watson,  Proc.  Am.  Acad.  9:117, 1894. 
Plate  50.     BuRSCALE. 

Erect  subshrub  or  herbaceous  perennial  with  a  woody  base,  1  to  10  dm.  high,  freely 
branched  from  the  base;  branches  stout,  obtusely  angled  or  nearly  terete,  densely  fur- 
furaceous  or  those  of  the  staminate  plants  nearly  naked,  glabrate  in  age,  the  bark  exfol- 
iating in  layers  from  the  old  woody  portions;  leaves  mostly  alternate  but  the  lower  ones 
opposite,  tapering  to  a  short-  or  long-winged  petiole,  varying  from  lanceolate  to  oblong- 
elliptic  or  obovate,  narrowed  at  base,  obtuse  at  apex,  2  to  5  cm.  long,  0.5  to  2.5  cm.  wide, 
more  or  less  sinuate-dentate  or  some  of  the  leaves  entire,  rather  thick  or  thinnish,  white 
with  a  dense  and  permanent  scurf;  flowers  dioecious,  the  staminate  in  glomerules  along 
the  branches  of  elongated  nearly  leafless  terminal  panicles,  the  pistillate  in  more  leafy 
panicles  or  racemes;  perianth  5-cleft  in  the  st^aminate  flowers,  wanting  in  the  pistillate; 
fruiting  bracts  on  stalks  2  to  20  mm.  long  (or  a  few  subsessile),  thick  and  spongious, 
united  nearly  to  the  apex,  subglobose  or  broadly  elliptic  in  outline,  8  to  14  mm.  long  and 
nearly  as  broad,  the  free  tips  often  beak-like,  the  faces  bearing  numerous  flattened,  irreg- 
ular, often  toothed  appendages,  these  commonly  longer  than  the  body;  seed  1.5  to  2  mm. 
long,  brown;  radicle  superior.   {Obione  acanthocarpa  Torrey,  Bot.  Mex.  Bound.  183,  1859.) 

Western  Texas  to  southern  Arizona,  Chihuahua,  and  San  Luis  Potosi.  Type  locality, 
plain  between  the  Burro  Mountains,  New  Mexico.  Collections:  Guadalupe,  105  miles 
southwest  of  San  Antonio,  Texas,  Palmer  1167  (Gr);  "western  Texas  to  El  Paso,  New 
Mexico,"  Wright  57S  (Gr,  NY,  US);  Franklin  Mountains  near  El  Paso,  Texas,  Rose 
17891  (NY,  US);  banks  of  the  Gila  River,  New-  Mexico,  August,  1880,  Greene  (Gr); 
Winslow,  Arizona,  Jones  102  (Gr);  vicinity  of  Torreon,  Coahuila,  Palmer  473  (Gr,  NY, 
UC,  US);  southwest  of  Parras,  Coahuila,  Palmer  1161  (US);  Sapio,  Sierra  Madre  Moun- 
tains, Chihuahua,  September  10,  1903,  Jones  (US);  Chihuahua  State,  Hartman  723  (Gr, 
NY,  UC,  US) ;  alkaline  plains,  Hacienda  de  Angostura,  San  Luis  Potosi,  Pringle  3775  (Gr, 
,  NY,  UC,  US,  type  collection  of  A.  pringlei  Standley,  minor  variation  2). 

MINOR  VARIATIONS  AND  SYNONYMS. 
1.  A  peculiarly  slender-stemmed  and  thin-leaved  form  has  been  collected  in  Texas  and  New  Mexico. 
The  stems  in  this  are  but  obscurely  farinose  and  even  the  leaves  are  only  thinly  covered  with  scales  and  there- 
fore greenish.  The  absence  of  complete  fruiting  specimens  would  render  ta.\onomic  recognition  impossible 
at  this  time,  even  if  it  could  be  demonstrated  that  the  form  is  other  than  an  ecad.  Representative  collections 
are:  southwest  of  San  Antonio,  Texas,  Palmer  1157  (US);  New  Mexico,  Wright  17S7  (US). 


A.    ACANTHOCARPA. — A    OBOVATA.  321 

2.  Atriplex  pringlei  Standley,  N.  Am.  Fl.  21:68,  1916. — Stems  erect  to  horizontally  spreading  from  the 
base,  the  whole  plant  only  1.5  to  3  dm.  high;  leaves  spatulate  or  narrowly  obovate,  densely  and  coarsely  white- 
furfuraceous,  mostly  entire  but  a  few  with  ob.scurely  sinuate-dentate  margins.  Type,  Hacienda  de  Angostura, 
San  Luis  Potosi,  Pringle  S776  (US).  This  was  placed  in  the  Nvilallianae  by  Standley,  and  there  is  no  question 
that  in  foliage  it  is  intermediate  between  that  group  and  A.  acanthocarpa.  No  leaves  can  be  found  on  the  type 
specimen  that  are  certainly  dentate,  but  that  the  tendency  is  present  is  indicated  by  dupUcates  of  the  types  at 
the  University  of  California  in  which  some  of  the  leaves  are  plainly  sinuate-dentate.  The  body  of  the  fruiting 
bracts  is  thicker  and  more  spongious  than  in  any  of  the  forms  of  nuttalli,  and  in  this  respect  the  specimens  are 
like  acanthocarpa.  Possibly  the  habit  and  foliage  characters  may  be  linked  with  others  of  greater  importance 
when  these  littls-known  Mexican  forms  are  studied  in  the  field  and  pringlei  may  then  be  reestablished  as  a 
species  or  at  least  as  a  subspecies. 

3.  Obione  acanthocarpa  Torrey,  Bot.  Mex.  Bound.  183,  1859.-^4.  acanthocarpa. 

RELATIONSHIPS. 

Together  with  A.  barclayana,  A.  obovata,  and  A.  nuttalli,  this  represents  an  early 
Mexican  stock  from  which  many  of  the  shrubby,  dioecious  Atriplexes  have  developed. 
The  connection  with  the  first-mentioned  of  these  is  seen  in  the  very  much  thickened 
fruiting  bracts,  while  in  nearly  all  of  its  other  features,  except  the  dentate  leaves,  it  is 
more  like  nuttalli.  In  the  extreme  form  the  fruiting  bracts  firmly  unite  to  form  a  spher- 
ical body  6  or  7  mm.  in  diameter,  the  surface  of  which  is  covered  with  short  spinose  pro- 
cesses. In  other  forms  the  body  is  smaller  but  the  processes  are  longer  and  much  flat- 
tened, resembling,  except  for  arrangement,  the  wings  on  the  bracts  of  A.  canescens, 
which  species  may  have  been  connected  with  acanthocarpa  at  some  remote  period. 
ECOLOGY  AND  USES. 

Atriplex  acanthocarpa  resembles  A.  obovata  somewhat,  but  is  more  open  and  branched. 
It  likewise  grows  in  alkaline  flats,  but  is  of  less  importance,  usually  mingling  with  the 
more  dominant  polycarpa  or  canescens. 

While  it  is  doubtless  grazed  to  a  slight  extent,  nothing  definite  is  known  of  its  uses. 

37.  ATRIPLEX  OBOVATA  Moquin,  Chenop.  Enum.  61,  1840.     Plate  50.     Broadscale. 

Erect  subshrub,  woody  at  least  at  the  base,  2  to  5  dm.  high;  branches  rigidly  erect  from 
a  much-branched  spreading  base,  not  angled,  gray-furfuraceous,  the  bark  exfoliating 
in  strips  from  the  old  basal  portions;  leaves  mostly  alternate,  the  lowest  opposite,  short- 
petioled,  obovate  or  broadly  elliptic,  tapering  to  the  base,  very  obtuse  or  even  retuse  at 
summit,  1  to  3.5  cm.  long,  0.5  to  2  cm.  wide,  entire  or  only  undulate,  thick,  firm,  nearly 
white  with  a  smooth,  compact  permanent  scurf;  flowers  dioecious,  the  staminate  in  small 
glomerules  along  the  spike-like  branches  of  oblong  terminal  nearly  naked  panicles,  the 
pistillate  in  small  clusters  in  the  axils  of  elongated  terminal  more  leafy  spikes,  these  some- 
times slightly  paniculate;  perianth  5-cleft  in  the  staminate  flowers,  wanting  in  the  pistil- 
late; fruiting  bracts  sessile  or  short-stalked,  compressed  or  only  slightly  convex,  united 
at  least  to  the  middle,  obovate  or  cuneate-orbicular,  4  to  5  mm.  long,  5  to  7  nun.  broad, 
the  summit  and  margins  sharply  toothed,  the  sides  smooth  or  with  a  few  small  tubercles  or 
crests  (tubercles  more  numerous  and  elongated  in  variety  tuberata  Macbride,  minor 
variation  4) ;  seed  2.4  to  2.8  mm.  long,  light  (or  reddish?)  brown;  radicle  superior. 

Northern  Arizona,  southern  Colorado,  and  western  Texas  to  Chihuahua  and  Zacatecas. 
Type  locaUty,  San  Luis  Potosi,  Mexico.  The  type  locality  was  originally  given  as  Peru, 
but  the  Berlandier  specimen,  which  is  the  type,  came  from  San  Luis  Potosi,  according  to 
Moquin  (in  De  Candolle,  Prodr.  13^:99,  1849)  and  according  to  a  label  with  a  portion  of 
the  type  in  the  Gray  Herbarium,  which  label  reads:  "Hacienda  del  Salad,  Saint  Louis 
Potosi,  1827."  Collections:  Arizona:  Adamana,  Griffiths  5121,  6125,  5126,  5128,  5129 
(US);  Navajo  Reservation,  rather  common  in  valleys,  Vorhies  27  (UC);  Winslow,  Jones 
4109  (Herb.  Jones,  type  of  A.  sabulosa  Jones,  minor  variation  3);  north  end  of  Carrizo 
Mountains,  Standley   747  (US);    Holbrook,    Rusby   795  (UC);   El  Sauzal,  September 


322  GENUS   ATRIPLEX. 

5,  1858,  Hayes  (Gr);  Aztec  ruins,  northwestern  New  Mexico,  Hall  11126  (UC);  near 
Tiznitzin.  northwestern  New  Mexico,  Wooton  2775  (UC);  southwestern  Colorado,  1875, 
Brandegee  (UC) ;  Tornillo  Creek,  western  Texas,  Havard  103  (Gr,  type  of  variety  tuberata 
Macbride,  minor  variation  4); El  Paso,  Texas,  Jones  J^ISS  (Gr,  US);  Comacho  Plains, 
Zacatecas,  Lloyd  253  (US) ;  type  collection,  Hacienda  del  Salad,  San  Luis  Potosi,  1827, 
Berlandier  1346  (Gr);  Mexico,  Gregg  462  (Gr,  NY,  type  collection  of  A.  greggi  Watson, 
minor  variation  1). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Atriplex  greggi  Watson,  Proc.  Am.  Acad.  9:11S,  1874. — Based  upon  Gregg's  No.  462  from  Mexico, 
which  is  the  typical  small-leaved  and  small-bracted  form  of  A.  obovata  Moquin,  the  type  collection  of  which  was 
also  cited  by  Watson  as  representing  his  species.     Quite  probably  Moquin's  name  was  overlooked  by  Watson. 

2.  A.  JONESI  Standley,  N.  Am.  Fl.  21 :65,  1916. — Based  upon  A.  sabulosa  Jones,  which  see. 

3.  A.  SABULOSA  Jones,  Contr.  West.  Bot.  11:21,  1903. — When  originally  described  this  was  not  compared 
with  A.  obovata,  which  doubtless  was  overlooked,  but  it  is  a  northern  large-leaved  and  large-bracted  form  of 
this  species.  Genuine  obovata  has  leaves  only  about  1  cm.  long  by  0.5  to  0.7  cm.  wide  and  bracts  correspondingly 
small.  In  the  type  of  sabulosa  the  leaves  are  about  2.5  cm.  long  by  1  cm.  and  more  wide,  the  bracts  6  mm. 
broad.  The  two  forms  are  not  entirely  geographic,  for  in  specimens  from  as  far  south  as  Zacatecas  (Lloyd  263) 
there  are  leaf-blades  as  large  as  1.7  by  0.9  cm.  and  bracts  5  mm.  broad;  while  in  some  from  El  Sauzal,  Ari- 
zona (September  5,  1858,  Hayes)  the  largest  blades  are  only  1.2  by  0.5  cm.  and  the  bracts  5  mm.  broad.  As 
intermediate  in  size  of  leaf  and  bracts  may  be  cited:  El  Paso,  Texas,  Jones  4183  (Gr);  western  Texas,  Wright 
572  (Gr).  After  changing  the  name  of  sabulosa  to  jonesi  (because  of  the  earlier  A.  sabulosa  Rouy),  Standley 
characterizes  this  as  having  bracts  smooth  or  rarely  slightly  tuberculate  on  the  sides,  while  obovata  is  described 
as  having  crested,  sparsely  tuberculate,  or  rarely  smooth  bracts  (Standley  in  N.  Am.  Fl.  21 :38  and  66,  1916). 
The  decidedly  unreliable  nature  of  this  character  is  now  well  known  (see  under  Criteria,  p.  242,  and  compare 
Macbride,  Contr.  Gray  Herb.  N.  S.  53:10, 1918).  Moreover,  the  original  description  of  o6wato  reads:  "bracteis 
*  *  *  disco  inappendiculatis."  It  is  true  that  most  of  the  large-leaved  northern  plants  have  broad  fruiting 
bracts  which  are  smooth  or  with  only  2  small  thickenings  on  the  side,  but  not  infrequently  there  may  be  found 
on  single  plants  all  variations  from  smooth  to  as  strongly  crested  as  in  any  yet  collected  in  Mexico  (e.  g.,  Winslow, 
Arizona,  at  the  type  locality  of  sabulosa,  Hall  11174,  UC).  It  seems,  therefore,  that  sabulosa  is,  at  the  most, 
only  an  ecologic  form  of  obovata.  This  conclusion  was  predicted  by  Standley  at  the  time  he  made  the  above- 
mentioned  transfer  of  names  (see  Bull.  Torr.  Club  44:425,  1917). 

4.  A.  OBOVATA  var.  tuberata  Macbride,  Contr.  Gray  Herb.  53: 11,  1918. — Marked  only  by  having  some  of 
the  fruiting  bracts  copiously  tuberculate.  Type  locality,  Tornillo  Creek,  Texas.  The  negative  value  of  the 
tubercle  character  as  a  taxonomic  criterion  is  indicated  under  No.  3. 

RELATIONSHIPS. 

This  species  is  most  closely  related  to  A.  nuttalli.  Both  seem  to  have  originated  in 
Mexico,  where  the  present  species  still  maintains  a  foothold.  The  fruiting  bracts  are 
broader  in  proportion  to  their  length  than  in  any  other  Atriplex  of  this  group  and  the 
seeds  are  considerably  larger. 

ECOLOGY  AND  USES. 

Atriplex  obovata  is  similar  to  A.  nuttalli  in  ecological  behavior,  but  it  is  less  adaptable, 
and  hence  is  more  restricted  in  range  and  habitat.  It  is  taller  and  looser  in  growth  and 
in  consequence  is  usually  not  a  mound-former.  It  sometimes  makes  a  pure  consocies  on 
alkaline  flats,  but  is  more  often  associated  with  Sarcobatus,  Suaeda,  or  Sporobolus  airoides, 
and  such  annuals  as  A .  powelli,  A .  argentea,  and  Salsola. 

This  species  has  much  the  same  grazing  value  as  nuttalli,  but  is  eaten  less  because  it 
grows  in  a  region  where  grass  is  more  abundant. 

38.  ATRIPLEX  NUTTALLI  Watson,  Proc.  Am.  Acad.  9:116,  1874.'     Plate  51. 

MOUNDSCALE. 

Erect  or  slightly  spreading  subshrub,  woody  at  the  base,  but  the  erect  or  ascending 
stems  mainly  herbaceous,  2  to  5  dm.  high;  branches  rigid,  not  angled,  gray  or  whitish  with 

'  The  reasons  for  retaining  this  name  instead  of  A.  gardneri,  as  called  for  by  the  botanical  codes,  are  stated  under  minor 
variation  18  (p.  327). 


A.    NUTTALLI.  323 

a  dense  scurf,  the  bark  becoming  dark  and  rough  only  on  the  old  basal  portions ;  leaves  all 
alternate  except  the  lower  ones  of  young  stems,  short-petioled  (sessile  in  subspecies  buxi- 
folia),  oblong  oblanceolate  or  spatulate  to  elliptic  or  ovate  (rarely  obovate),  mostly  taper- 
ing to  the  base,obtuseatapex,1.5  to5cm.  long,  0.2  to  2  cm.  wide,  strictly  entire,  thick  and 
firm,  gray  or  greenish-white  with  a  dense  and  permanent  scurf;  flowers  dioecious  (rarely 
monoecious,  see  note  under  Relationships,  p.  329),  the  staminate  in  glomerules  of  ter- 
minal spikes  or  narrow  panicles  a  few  centimeters  long,  this  inflorescence  leafy  in  the  lower 
part,  the  pistillate  in  long,  compact  terminal  spikes  and  spike-like  panicles  leafy  below; 
perianth  5-cleft  in  the  staminate  flowers,  wanting  in  the  pistillate;  fruiting  bracts  sessile 
or  stalked  (especially  in  subspecies /aZcaia),  thick  and  somewhat  spongious,  united  nearly 
to  summit,  lanceolate  to  broadly  elliptic  or  cuneate-oblong,  4  to  7  mm.  long,  2  to  5  mm. 
broad  (slightly  larger  when  long-appendaged),  the  free  tips  sometimes  beak-like,  more 
or  less  dentate  across  the  summit  and  often  also  down  the  sides,  the  faces  smooth  or  tuber- 
culate  or  with  variously  shaped  appendages;  seed  1.5  to  2  mm.  long,  brown;  radicle 
superior. 

Saskatchewan  and  South  Dakota  to  western  Nebraska  (where  introduced?),  New 
Mexico,  Arizona,  northwestern  California,  eastern  Washington,  and  Alberta. 

SUBSPECIES. 

All  of  the  following  subspecies,  with  the  exception  oifalcata,  are  based  upon  characters 
which  are  not  constant.  It  must  be  expected,  therefore,  that  some  specimens  can  not  be 
definitely  placed. 

Key  to  Subspecies  of  AlHplex  nuttalli. 
Fniiting  bracts  orbicular-ovate  or  oblong  to  cuneate-oblong,  often  globoid  when  appendaged, 
terminal  tooth  sometimes  beak-like  but  never  attenuate. 
Leaves  oblong-linear  to  spatulate  or  nearly  obovate,  usually  elongated  and  broadest 
above  the  middle. 
Fruiting  bracts  broadest  at  or  below  the  middle. 

Leaves  oblong,  spatulate,  or  obovate;  bracts  usually  appendaged (a)  typiea  (p.  323). 

Leaves  narrower,  hnear-oblong,  sides  nearly  parallel  except  at  the  narrowed 

base;  bracts  usually  smooth (6)   tridentata  (p.  324). 

Fruiting  bracts  broadest  above  middle,  usually  smooth.     (Leaves  narrow.) (c)  gardneri  (p.  324). 

Leaves  broadly  elliptic  or  ovate,  short,  usually  broadest  at  or  below  the  middle. 

Leaves  acute  at  base,  mostly  petioled (d)  cuneata  (p.  324). 

Leaves  obtuse  at  base,  sessile (e)   buxifolia  (p.  325). 

Fruiting  bracts  fusiform  with  attenuate  beak  2  mm.  or  more  long.     (Leaves  Unear-spatulate.)  (/)  falcata  (p.  32.5). 

38a.  Atripex  nuttalli  typica. —  Stems  erect  from  a  decumbent  woody  very 
freely  and  intricately  branched  base;  leaves  oblong  or  spatulate  or  narrowly  obo- 
vate, obtuse,  3  to  5  cm.  long,  0.5  to  1  cm.  wide,  tapering  to  a  short  petiole;  fruiting 
bracts  ovate  or  orbicular-ovate  in  outline,  sessile  or  an  occasional  one  short-stalked,  4 
to  6  mm.  long,  sharply  few-toothed  at  summit,  the  terminal  pair  of  teeth  commonly 
forming  a  flat  lanceolate  beak,  the  sides  covered  with  numerbus  conspicuous  sharp 
appendages,  some  of  which  commonly  are  more  or  less  flattened.  (.4.  nuttalli  Watson, 
Proc.  Am.  Acad.  9:116,  1874.)  Alkaline  plains  and  hillsides,  Saskatchewan  to  eastern 
Wyoming,  central  Colorado,  northern  Utah,  Idaho,  and  Alberta;  also  in  western  Ne- 
braska (where  introduced  in  stock-cars,  according  to  Bates,  Asa  Gray  Bull.  6:35-37, 
1898)  and  a  doubtful  collection  from  northwestern  Arizona.  Tjrpe  locality,  not  defi- 
nitely stated.  Collections:  Round  Valley  Lake,  Saskatchewan,  Macoun  and  Herriot 
76722  (NY);  Leeds,  North  Dakota,  1900,  Lunell  (Or);  Owl  Butte,  South  Dakota, 
Griffiths  339  (US);  Centennial,  Albany  County,  Wyoming,  Goodding2114  (NY,  UC,  US); 
Delta,  Colorado,  Coiuen  Ji.071  (Or,  R,  US,  type  collection  of  A.  oblanceolata  Rydberg, 
minor  variation  14) ;  Price,  Utah,  June  20, 1898,  Stokes  (UC) ;  Salt  Lake  City,  Utah,  July 
24,1879,  Jones  (NY);  Fort  Mojave,  Arizona,  April,  1884,  Lemmon  (UC,  data  doubtful) ; 
Blackfoot  County,  Montana,  Griffiths  and  Lange  282  (US);  Helena,  Montana,  July  29, 
1898,  Brandegee  (UC).     Additional  stations  where  either  this  or  one  of  the  two  next 


324  GENUS   ATRIPLEX. 

following  subspecies  occurs,  all  represented  by  specimens  in  the  Rocky  Mountain  Her- 
barium of  the  University  of  Wyoming,  are  Walhalla,  in  North  Dakota;  northwestern 
and  eastern  Harding  County,  in  South  Dakota;  Laramie,  Point  of  Rocks,  Sweetwater 
River,  Big  and  Little  Laramie  Rivers,  Granger,  Poison  Spider  Creek,  Buffalo,  Howell 
Lakes,  Seven-mile  Lakes,  Red  Desert,  Steamboat  Lake,  Wamsutter,  Leucite  Hills, 
North  Fork  Vermillion  Creek,  and  Carter  (Uinta  County)  in  Wyoming;  Montrose  in 
Colorado;  Mendon  (Cache  County)  and  Cannonville  in  Utah;  and  Clyde  (Blaine 
County)  and  Falks  (Canon  County)  in  Idaho. 

386.  Atriplex  nuttalli  tridentata  (Kuntze).  Stems  strictly  erect  from  a  com- 
pact base,  the  decumbent  portion  short  and  the  plants  therefore  narrow;  leaves 
oblong  or  linear-oblong,  obtuse,  2.5  to  5  cm.  long,  0.3  to  0.8  cm.  wide,  narrowed  to  a 
subsessile  base;  fruiting  bracts  orbicular-ovate,  with  a  shortly  cuneate  base,  broadest 
below  the  middle,  sessile,  4  to  5  mm.  long,  broad-margined,  with  usually  3  prominent 
and  several  smaller  teeth  at  summit,  the  middle  tooth  often  the  largest,  the  sides  smooth 
or  rarely  with  a  few  small  tubercles.  {A.  tridentata  Kuntze,  Rev.  Gen.  PI.,  546,  1891.) 
Wyoming,  northern  Colorado,  and  Utah.  Type  locality,  near  Corinne,  Utah.  Col- 
lections: Sweetwater  County,  Wyoming,  Nelson  3667  (Gr);  Point  of  Rocks,  Wyoming, 
Nelson  44^9  (Gr,  R,  type  collection'  of  A.  pabularis  Nelson,  minor  variation  15); 
Granger,  Hams  Fork,  Wyoming,  Nelson  3893  (NY,  US);  Uinta  County,  Wyoming, 
Goodding  1179  (Gr,  form  approaching  minor  variation  4,  A.  eremicola  Osterhout). 

38c.  Atriplex  nuttalli  gardneri  (Moquin). — Stems  erect  from  a  woody  branch- 
ing base;  leaves  narrowly  oblong  or  oblanceolate,  obtuse,  1.5  to  4  cm.  long,  0.3  to  1 
cm.  wide,  tapering  to  a  short  petiole;  fruiting  bracts  oblong  with  a  cuneate  base  or 
narrowly  obovate,  broadest  above  the  middle,  sessile,  4  to  6  mm.  long,  with  several  prom- 
inent teeth  across  the  summit,  the  middle  tooth  usually  the  largest,  the  sides  smooth  or 
with  a  few  tubercles.  {Ohione  gardneri  Moquin,  in  DeCandolle,  Prodr.  13^:114,  1849.) 
Alkaline  plains  and  slopes  of  southern  Wyoming,  northern  Colorado,  and  southern  Idaho. 
Type  locality,  along  the  Platte  River.  Collections:  Type  collection.  La  Platte  River, 
Gordon  (Gr) ;  Laramie  River,  Wyoming,  Nelson  8174  (Gr) ;  Big  Laramie  River,  Wyoming, 
E.  Nelson  736  (Gr);  8  km.  east  of  Medicine  Bow,  Wyoming,  September  10,  1919,  Hall 
(CI,  a  broad-leaved  form);  Steamboat  Lake,  southern  Wyoming,  July  21,  1898,  Osterhout 
(Gr);  southern  Wyoming,  July,  1896,  Osterhout  (Herb.  Osterhout,  type  of  A.  eremicola 
Osterhout,  minor  variation  4) ;  Howell  Lakes,  Albany  County,  Wyoming,  E.  Nelson  4463 
(NY,  same  variation);  Howell  Lakes,  Wyoming,  A.  and  E.  Nelson  6910  (Gr,  bracts  partly 
typical,  see  fig.  46);  Point  of  Rocks,  Wyoming,  Hall  10935  (UC,  see  note  under  minor 
variation  15);  between  Strevell  and  Albion,  Idaho,  September  17,  1919,  Hall  (UC). 

38(i.  Atriplex  nuttalli  cuneata  (Nelson). — Stems  erect  from  a  decumbent,  decid- 
edly woody,  much  branched  base;  leaves  broadly  elliptic,  very  obtuse,  2  to  6  cm.  long 
including  the  petiole  or  rarely  only  1.2  cm.  long  and  sessile,  0.6  to  2.5  cm.  wide, 
cuneately  narrowed  to  a  short  petiole  or  base;  fruiting  bracts  globoid  in  outline  or  slightly 
elongated,  sessile  or  short-stalked,  5  to  7  mm.  long,  irregularly  toothed  at  summit,  the 
sides  with  numerous  conspicuous  crest-like  appendages,  these  commonly  more  or  less 
flattened  (fig.  45,  a,  h.).  {A.  cuneaia  Nelson,  Bot.  Gaz.  34:357,  1902.)  Southwestern 
Colorado,  northern  New  Mexico,  northern  Arizona,  and  southern  Utah.  Type  locahty, 
Emery,  Utah.  Collections:  Alkaline  plains  at  Mesa  Grande,  along  the  Gunnison  River, 
Colorado,  Purpus  82,  209  (UC) ;  Grand  Junction,  Colorado,  common  on  alkaline  plateaus, 
Hall  11048  (UC);  San  Juan  Plains,  southwestern  Colorado,  Brandegee  1086,  in  part 

■  Nelson's  4429  is  labeled  as  the  type  in  the  Rocky  Mountain  Herbarium  and  his  3712,  from  the  same  locality,  is  there 
indicated  as  a  cotype.  The  latter  number  is  cited  Brst  in  connection  with  the  original  description.  Both  collections  are  of 
the  pabularit  form. 


A.   NTJTTALLI.  325 

(UC) ;  Mancos,  southern  Colorado,  Baker,  Earle,  and  Tracy  420  (Gr,  UC) ;  near  Farming- 
ton,  San  Juan  County,  New  Mexico,  Standley  7066  (US,  type  of  A.  neo-mexicana  Stand- 
ley,  minor  variation  10) ;  5  and  8  km.  south  of  Shiprock  Station,  San  Juan  County,  New 
Mexico,  Hall  11143,  11144  (CI,  UC);  dry  hills  near  Shiprock,  New  Mexico,  Standley 
7278  (US);  type  collection,  2,140  m.  altitude,  June  16,  1894,  Jones  5443  (R,  NY,  UC); 
same  locality  and  date,  Jones  5445r  (US);  just  south  of  Green  River  Station,  Utah, 
abundant,  HaU  11036  (UC). 


Leaves  of  Atnplex  nuttalli:  a,  b,  subspecies  cuneata  from 
Shiprock,  New  Mexico  (686245  US) ;  c,  d,  subspecies  buri- 
folia  from  Sheep  Creek,  Wyoming   (393362  US).     AU  X  1. 


38e.  Atriplex  nuttalli  buxifolia  (Rydberg). — Stems  erect  or  ascending  from  a 
decumbent,  very  woody  base;  leaves  elliptic,  obtuse,  2  cm.  or  less  long,  0.5  to  0.8  cm.  wide, 
abruptly  narrowed  to  an  obtuse  sessile  base;  fruiting  bracts  ovate  or  globoid  in  outline, 
sessile  or  nearly  so,  4  to  5  mm.  long,  irregularly  toothed  at  summit,  the  sides  with  con- 
spicuous crest-like  appendages  which  are  more  or  less  flattened  or  these  appendages 
wanting  (fig.  45,  c,  d).  {A.  buxifolia  Rydberg,  Bull.  Torr.  Club  39:  311,  1912.)  Dry 
plains  of  eastern  Wyoming.  Type  locality,  Dayton,  Sheridan  County,  Wyoming.  Col- 
lections: Type  collection,  1,220  m.  altitude,  September,  1899,  Tweedy  2456  (NY);  Sheep 
Creek,  Wyoming,  August  21,  1899,  Schuchert  (US). 

38/.  Atriplex  nuttalli  falcata  (Jones). — Stems  erect  or  ascending  from  a  decum- 
bent base,  the  woody  portion  very  short;  leaves  linear-spatulate  or  rarely  oblong-spatu- 
late,  commonly  more  or  less  falcate,  2  to  4  cm.  long,  0.2  to  0.7  cm.  wide,  tapering  to  a 
short  petiole;  fruiting  bracts  lanceolate  or  narrowly  ovate  in  vertical  section,  forming  an 
approximately  fusiform  fruit,  sometimes  long-stalked  but  often  sessile  (even  in  the  type 
specimen),  4  to  6  mm.  long  exclusive  of  stalk  (only  3  or  4  mm.  broad),  the  free  tips  con- 
spicuously elongated  and  beak-like  (2  or  3  mm.  long),  the  sides  with  few  to  numerous  con- 
spicuous sharp  appendages,  these  slightly  or  not  at 'all  flattened,  or  the  sides  sometimes 
smooth  (in  A.  n.  anomala  Jones,  minor  variation  11).  {A.  nuttalli  var.  falcata  Jones, 
Contr.  West.  Bot.  11 :  19,  1903.)  Northern  part  of  the  Great  Basin;  western  Montana  to 
northern  Utah  (according  to  Jones),  Nevada,  northeastern  California,  eastern  Washing- 
ton, and  Idaho.  Type  locality,  Weiser,  Idaho.  Collections:  Horse  Valley,  southwestern 
Montana,  Hall  11503,  11561  (UC);  Dolly  Varden  Smelter,  eastern  Nevada,  July  24, 
1891,  Jones  (Herb.  Jones,  type  of  A.  nuttalli  anomala  Jones,  minor  variation  11);  Battle 
Mountain,  Elko  County,  Nevada,  Kennedy  3074  (US);  Winnemucca  Lake,  Nevada, 
Kennedy  1974  (US,  young  and  doubtful) ;  16  to  24  km.  west  of  Amedee,  Lassen  County, 
California,  June  24,  1897,  Jones  (Herb.  Jones);  dry  hillsides  near  Willow  Creek  Valley, 
Lassen  County,  California,  Davy  3402  (UC);  near  Beattys,  Butte  County,  Oregon, 
Leiberg  2611  (US);  dry  ground  at  the  Narrows,  Harney  County,  Oregon,  Peck  1677  (Gr) ; 
Powder  River  Valley,  eastern  Oregon,  Cusick  1928  (Gr,  US);  near  Egbert  Springs,  Doug- 
las County,  Washington,  Sandberg  and  Leiberg  S49  (Gr,  NY,  UC,  US) ;  type  collection, 
July  7,  1899,  Jones  (Herb.  Jones) ;  Antelope  Valley,  Idaho,  Henderson  3635  (US) ;  Twin 
Falls  and  Shoshone  Falls,  Idaho,  Nelson  and  Macbride  1351  (NY,  UC,  US);  Pocatello, 
Idaho,  Palmer  407  (Gr,  US);  Leadore,  Lemhi  Valley,  eastern  Idaho,  Hall  11506  (UC). 


326  GENUS   ATRIPLEX. 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Atriplex  acanthocarpa  var.  cu>fEATA  Jones,  Contr.  West.  Bot.  11:20,  1903. — Baaed  upon  A.  cuneata 
Nelson,  which  is  here  treated  as  a  subspecies  of  A.  nuUalli.  No  reasons  were  given  for  the  reduction  to  ocon- 
ihocarpa.  If  this  arrangement  were  accepted,  then  all  of  the  forms  of  nuttalli  should  go  with  it.  This  seems 
unnecessary,  for  although  the  two  are  closely  related,  the  heavy  and  strictly  entire  leaves  of  cuneata  and  its 
allies  are  very  unlike  those  of  acanthocarpa.  Even  when  the  fruiting  bracts  are  heavily  appendaged,  as  in 
cuneata,  and  therefore  exceptionally  large  in  total  expanse,  the  body  itself  is  never  so  thick  nor  turgid  as  in 
acanthocarpa. 

2.  A.  BUXIFOLIA  Rydberg,  Bull.  Torr.  Club  39:311,  1912.— A.  nuttalli  huxifolia. 

3.  A.  CUNEATA  Nelson,  Bot.  Gaz.  34:  357,  1902. — A.  nuttalli  cuneata,  with  the  exception  of  two  of  the  cited 
specimens,  i.  e.,  Wright  573,  which  is  A.  acanthocarpa,  and  the  plant  from  Holbrook,  Arizona,  which  is  A. 


4.  A.  EREMicoLA  Osterhout,  Bull.  Torr.  Club  25:  284,  1898. — A.  nuttalli  gardneri.  The  type,  which  came 
from  southern  Wyoming,  is  a  plant  in  which  the  fruiting  bracts  are  very  smooth,  the  edges  nearly  parallel, 
but  cuneately  narrowed  at  base  and  slightly  enlarged  at  summit  through  the  development  of  herbaceous 
teeth.     (Fig.  46,  w  to  z.) 


^      © 


FiQ.  46. — Variation  in  fruiting  bracts  of  Atriplex  nuttalli:  a  to  d,  from  one  plant  of  subspecies  typica  (Centennial,  Wj-oming, 
128609  UC):  e  to  g.  from  another  plant  of  typica  (Price.  Utah,  110313  UC);  h  to  k,  from  one  plant  of  subspecies 
tridentata  (west  of  Rock  Springs,  Wyoming,  205252  UC};  I  to  p,  from  one  plant  of  subspecies  gardneri  (Little 
Laramie  River,  Wyoming,  35325  R) ;  g  (o  »,  from  another  collection  of  gardneri,  all  probably  from  a  single  plant 
(Laramie,  Wyoming,  205354  UC);  w  to  z,  from  another  collection  of  gardneri  (southern  Wyoming,  type  of  A. 
eremicola,  minor  variation  4).     All  X  2. 

5.  A.  FALCATA  Standley,  N.  Am.  Fl.  21:68,  1916.— A.  mittalli  falcata. 

6.  A.  FRUTicuLOSA  Osterhout,  Bull.  Torr.  Club  25:  207,  1898.— Changed  by  Osterhout  to  A.  eremicola 
because  of  the  earlier  A.  fruticulosa  Jep.son.     (See  under  No.  4.) 

7.  A.  GARDNERI  Standley,  1.  c,  66,  1916. — Based  upon  Obione  gardneri,  which  see. 

8.  A.  GARDNERI  var.  tridentata  Macbride,  Contr.  Gray  Herb.  N.  S.  53: 11,  1918. — Based  upon  A.  triden- 
tata, which  see. 

9.  A.  gordoni  Hooker,  Jour.  Bot.  and  Kew  Misc.  5:261,  1853. — Based  upon  Obione  gardneri,  which  see. 
The  specific  name  was  changed  by  Hooker,  since  it  was  Gordon  (not  Gardner)  who  collected  the  tj'pe  specimen. 

10.  A.  NEOMExiCANA  Standley,  1.  c,  67,  1916. — A  form  of  A.  nuttalli  differing  from  subspecies  cuneata, 
with  which  it  was  collected  in  northwestern  New  Mexico,  only  in  the  remarkable  foliaceous  development  of 
the  free  tips  of  the  bracts.  These  are  orbicular-rhombic  and  as  wide  as  or  wider  than  the  body.  The  relation 
of  tliis  to  the  usual  form  requires  further  field  study. 

11.  A.  NUTTALLI  var.  anomala  Jones,  Contr.  West.  Bot.  11:  19,  1903. — The  same  as  A.  nuttalli  falcata, 
except  that  the  fruiting  bracts  are  smooth  on  the  faces  and  margins,  or  only  occasionally  with  a  few  teeth  or 
murications.  According  to  Jones,  intermediates  occur  in  the  Green  River  Basin,  Wyoming,  and  in  western 
Utah.  Most  of  the  specimens  cited  under  subspecies  falcata,  including  the  type,  exhibit  both  appendaged 
and  smooth  bracts.     Type  locality  of  anomala,  Dolly  Varden  Smelter,  eastern  Nevada. 

12.  A.  NUTTALLI  var.  falcata  Jones,  1.  c. — A.  nuttalli  suhspecies  falcata. 

13.  A.  nuttalli  var.  utahensis  Jones,  1.  c. — A  narrow-leaved  form  of  A.  nuttalli  typica.  The  description 
applies  better  to  subspecies  tridentata,  but  the  leaves  in  the  type  specimen  are  spatulate  rather  than  linear, 
and  very  obtuse.  Representative  leaves  measure  2  to  2.5  cm.  long  by  3  to  5  mm.  wide  at  the  broadest  part, 
i.  e.,  above  the  middle.     The  type  is  from  Salt  Lake  City,  Utah  {Jones  1760). 

14.  A.  oblanceolata  Rydberg,  Bull.  Torr.  Club  31:403,  1904. — A  low  form  of  A.  nuttalli  typica  and 
common  with  it.     Described  as  differing  also  in  having  short-putioled  leaves,  brown  staminate  flowers,  and  a 


A.    NUTTALLI.  327 

whiter  tomentum,  but  none  of  these  features  are  sufficiently  well-marked  to  be  of  service  in  distinguishing 
this  from  true  nutlalli.     Type  locality,  Delta,  Colorado. 

15.  A.  PABULAEis  Nelson,  Bull.  Torr.  Club  25:  203,  1898.— 4.  nitttaUi  tridentata.  This  is  a  form  with 
crowded  strictly  erect  leafy  stems  clustered  on  a  very  short  woody  base,  the  branches  of  which  are  slightly 
spreading.  Thus  the  plants  come  to  form  close  rounded  tufts.  The  bracts  are  about  as  in  typical  tridentata  but 
some  of  them  tend  to  be  broadest  toward  the  summit,  thus  approaching  subspecies  gardneri  (fig.  46).  At 
the  type  locality,  namely.  Point  of  Rocks,  Wyoming,  some  plants  with  the  habit  of  pabidaris  have  bracts  so 
broad  above  that  they  are  referred  to  subspecies  gardneri  (Hall  10935).  As  far  as  known  the  pahvlaris  form 
is  confined  to  highly  alkaline  clays  of  low  flats  immediately  adjacent  to  saline  streams. 

16.  A.  PABULARis  EREMicoLA  Nclson,  in  Coulter  and  Nelson,  Man.  Rocky  Mt.  Botany,  168,  1909. — Based 
upon  A.  eremicola  Osterhout,  which  see. 

17.  A.  TRIDENTATA  Kuntze,  Rev.  Gen.  PI.  546,  1891. — A.  nvtialli  tridentata. 

18.  Obione  gardneri  Moquin,  in  De  Candolle,  Prodr.  13':  114,  1849.— A.  nultalli  gardneri.  According 
to  both  the  International  and  American  Codes  this  form  should  be  taken  as  the  type  of  the  collective  species, 
the  name  of  which  would  then  become  Atriplex  gardneri  (Moquin)  Standley.  Under  this  arrangement  all 
of  the  subspecies  here  assembled  would  be  transferred  to  A.  gardneri.  The  reasons  for  retaining  A.  nuttalli  as 
the  inclusive  name  are  that  it  has  become  well  established  in  the  literature,  that  its  typical  form  is  abundant 
and  well-known  to  botanists,  and  that  if  the  other  name  were  adopted  there  would  still  remain  a  difference  of 
opinion  as  to  whether  or  not  it  should  be  corrected  to  gordoni,  as  proposed  by  Hooker  (Jour.  Bot.  and  Kew 
Misc.  5:  261,  1853). 

RELATIONSHIPS. 

Atriplex  nuttalli  belongs  to  a  small  group  of  dioecious  species  which  stand  intermediate 
between  the  herbaceous  and  the  truly  shrubby  forms.  Its  derivation  doubtless  was  from 
a  Mexican  stock,  which  yielded  also  such  semi-shrubby  species  as  A.  barclayana,  A. 
acanthocarpa,  and  A.  obovata.  In  the  process  of  its  northward  migration  it  left  these 
forms  behind,  both  geographically  and  phylogenetically,  so  that  it  has  now  come  to 
inhabit  the  alkaline  plains  and  slopes  from  the  southern  Rocky  Mountains  and  Great 
Basin  northward  and  has  developed  a  combination  of  essential  characters  not  found  in 
any  of  the  others.  The  only  related  species  which  grows  well  within  its  area  is  A. 
corrugata,  a  still  less  shrubby  form  with  its  own  peculiar  characters,  as  will  be  later 
indicated. 

In  the  process  of  establishing  itself  in  the  extensive  area  now  occupied,  the  original 
nuttalli  stock  diverged  into  several  subspecies  and  a  large  number  of  minor  variations. 
All  of  these  are  so  closely  held  together  by  intermediate  forms  that  the  separation  into 
district  species  is  impracticable.  Standley's  8  species,  diagnosed  in  the  North  American 
Flora,  are  based  upon  features  which  field  study  and  the  abundance  of  recent  collections 
have  demonstrated  to  be  unstable.  The  only  one  which  stands  out  distinctly  over  most 
of  its  area  is  falcata.  This  is  based  upon  its  narrow  fruiting  bracts,  and,  although 
exact  intermediate  forms  have  not  as  yet  been  found,  the  character  is  of  such  a  nature 
that  it  may  be  expected  to  vary.  Jones,  the  original  sponsor  of  falcata,  gave  it  varietal 
rank  under  nuttalli. 

The  first  three  subspecies  form  a  very  close  group,  and  since  they  occupy  the  same 
region,  it  is  questionable  if  all  should  not  be  treated  as  one.  But  the  peculiar  bracts 
of  subspecies  gardneri  are  quite  distinctive  in  the  extreme  form,  being  decidedly  broadest 
above  and  with  margins  uniformly  narrowed  toward  the  base.  The  bracts  are  thus 
cuneate-oblong  with  a  truncate  summit.  However,  the  sides  are  sometimes  so  nearly 
parallel  that  it  is  difficult  to  say  whether  the  bracts  belong  to  this  or  to  subspecies  triden- 
tata (e.  g.,  in  Nelson  3667  from  Sweetwater  County,  Wyoming,  and  in  Hall  10935  and 
Nelson  U^9,  both  from  Point  of  Rocks,  Wyoming,  the  latter  the  type  of  A.  pabularis 
Nelson,  minor  variation  15).  A  few  of  the  shapes  are  shown  in  figure  46.  The  two 
subspecies  of  this  group  with  bracts  broadest  below,  i.  e.,  typica  and  tridentata,  differ 
from  each  other  in  habit  as  well  as  in  the  characters  used  in  the  chart.  The  latter  is  the 
less  woody  at  base  and  the  strictly  erect  stems  form  a  close,  almost  columnar  plant. 
The  tendency  toward  the  absence  of  appendages  on  the  bracts  is  tentatively  employed 


328 


GENUS   ATRIPLEX. 


as  a  distinguishing  feature,  since  it  seems  to  run  parallel  with  habital  and  foliage  c  harac- 
ters.  But  its  variability  in  other  species  and  the  absence  of  entire  constancy  even 
here,  as  shown  in  plate  51,  also  figure  46,  suggest  that  further  field  studies  may  nullify 
its  criterial  value.  The  lack  of  constancy  is  mentioned  in  the  original  descriptions  of 
nuttalli  and  gardneri. 


0 


Lvs.  oblong  or  spafu-  Lvs.  oblong- 

late  or  nearly  obovate;      with  narrow  base; 
bracts  mostly 


bracts  mostly  appe 
aged 


appendaged 


Bracfs  broadest  above, 
usually  not  append- 
aged; (lvs.  narrowly 
oblong  oroblanceo- 


Lvs.  elongated,  oblo 
linear  to  spatulate  c 
obovate,  tending  to 
broadest  above  the 
middle 


Bracts  broader  than  fi 
form,  usually  ovate  or  c 
long  to  orbicular. 


Lvs.  short,  broadly 
elliptic  to  ovate,  tend- 
ing to  be  broadest 


Bracts  fusiform, 

uate  beak  2  mm.  or  more 

long.  (Lvs.  linear-spatulate) 


Fio.  47. — Phylogonetic  chart  of  the  subapeciea  of  Alrivlei 


A.    NUTTALLI,  329 

Subspecies  cuneata  and  huxifolia  are  more  southerly  in  their  distribution.  This, 
together  with  their  shorter  and  relatively  broader  leaves  and  bracts,  the  latter  with 
prominent  flattened  appendages,  suggests  a  former  connection  with  such  related  species 
as  obovata  and  acanthocarpa.  The  compression  of  the  appendages  occurs  at  times  also 
in  typica  and  is  too  variable  to  be  depended  upon  for  purposes  of  identification. 

Although  almost  always  dioecious,  A.  nuttalli  is  occasionally  monoecious.  For 
example,  on  the  plains  south  of  Grand  Junction,  Colorado,  where  the  plants  are  mostly 
unisexual,  a  few  specimens  with  the  usual  naked  terminal  spikes  of  staminate  flowers 
have  also  an  abundance  of  well-formed  and  apparently  fertile  pistillate  flowers  in  the 
upper  leaf-axils  {Hall  IIO48,  UC). 

ECOLOGY. 

Atriplex  nuttalli  is  the  most  characteristic  dominant  of  strongly  alkaline  clay  soils 
throughout  the  larger  portion  of  the  sagebrush  association  of  the  Great  Basin,  and  in  the 
northwestern  portion  of  the  mixed  prairie.  It  is  especially  abundant  in  western  Wyoming 
and  Colorado,  Utah,  and  southern  Idaho,  where  it  covers  thousands  of  square  miles  of 
saline  plains  and  bad-land  slopes.  Owing  to  the  resistance  it  affords  to  wind  and  water 
erosion,  the  plants  on  plains  occur  almost  universally  on  low  mounds  6  inches  to  a  foot 
high  and  a  foot  or  two  across,  simulating  dunelets.  It  shares  this  habit  with  its  constant 
associate  in  the  heart  of  its  region,  namely,  A.  corrugata.  On  the  strongly  alkaline 
slopes  of  Mancos  shale  and  other  bad-land  formations,  nuttalli,  usually  with  corrugata, 
forms  the  first  perennial  associes  of  the  xerosere,  following  immediately  the  pioneer 
annual  communities,  such  as  A.  saccaria,  A.  graciliflora,  and  Eriogonum  infiatum.  On 
the  extensive  plains  at  the  base  of  such  ranges  it  lies  in  contact  with  Sarcobatus  and 
Chrysothamnus  nauseosus  consimilis  in  the  valleys,  and  A.  confertifolia  on  less  alkaline 
slopes  or  on  rocky  ridges.  The  spaces  between  the  mounds  are  often  covered  with 
annuals,  of  which  A.  powelli,  A.  argentea,  A.  rosea,  and  Eriogonum  inflatum  are  the  most 
important.  The  most  adaptable  of  the  subspecies  appears  to  be  falcata,  which  ranges 
from  saline  valleys  with  Sarcobatus  and  Suaeda  to  uplands,  where  it  occurs  with  Artemisia 
tridentata  and  frigida.  According  to  Kearney  and  his  associates,  the  salt-content  of  the 
first  foot  in  the  Sarcobatus-Atriplex  community  of  the  Tooele  Valley  in  which  nuttalli 
was  found,  ranges  from  0.08  to  0.61  per  cent,  while  for  the  fourth  and  fifth  feet  the  aver- 
ages were  1.15  and  1.58  per  cent  respectively.  At  Tucson  the  salt-content  ran  much 
higher,  as  it  undoubtedly  does  on  many  bad-land  slopes,  namely,  as  high  as  3.5  per  cent 
in  the  first  foot,  3.3  per  cent  in  the  second  foot,  and  2.5  per  cent  in  the  third. 

USES. 

This  is  an  important  browse  plant  in  the  alkaline  districts  where  it  grows.  Stockmen 
in  eastern  Utah  report  it  as  very  good  for  cattle  and  sheep  after  the  snow  leaves  in  the 
spring.  In  Wyoming,  also,  where  it  makes  dense  stands  in  low  moist  places  along  alkaline 
streams,  it  is  said  to  furnish  large  amounts  of  fodder  relished  by  sheep.  Like  other 
saltbushes,  however,  it  is  seldom  if  ever  eaten  by  choice  to  the  exclusion  of  other  foods. 
Doubtless  an  extensive  diet  of  this  plant  alone  would  lead  to  injurious  effects  similar 
to  those  of  the  related  A.  corrugata,  which  is  pretty  well  known  to  be  poisonous.  Knight, 
Hepner,  and  Nelson  report  on  A.  nuttalli  as  follows: 

"This  is  the  most  important  of  the  native  salt-bushes  (in  Wyoming)  ....  It  is  readily  eaten  by 
stock  and  endures  close  grazing.  Where  it  is  cropped  continuously,  it  becomes  matted  and  sends  up  numerous 
leafy  shoots.  It  is  very  common  in  many  parts  of  Wyoming  and  in  the  Red  Desert  furnishes  a  large  part  of 
the  winter  forage.  It  readily  reseeds  and  maintains  itself  where  once  established.  Occasionally  it  spreads 
into  fallow  fields  and  here  makes  a  thrifty  growth."     (Wyo.  Exp.  Sta.  Bull.  65:  46,  1905.) 

A  chemical  analysis  is  given  in  connection  with  this  report.  An  earlier  analysis  given 
as  for  this  plant  by  Forbes  and  Skinner  (Ariz.  Exp.  Sta.  Rep.  13:269,  1902)  applies  to 
A.  canescens,  there  having  been  an  error  in  the  determination  of  the  material  examined. 


330  GENUS   ATRIPLEX. 

39.  ATRIPLEXCORRUGATA  Watson,  Bot.Gaz.  16:345,  1891.     Plate  51.     Matscale. 

Spreading  subshrub,  woody  at  the  base,  forming  dense  leafy  mats,  1  to  2  dm.  high; 
branches  decumbent  at  base  but  the  flowering  stems  strictly  erect,  slender,  not  angled, 
densely  furfuraceous,  the  bark  breaking  in  age  into  fibrous  sheaths  on  the  old  parts; 
leaves  mostly  opposite,  the  upper  alternate,  sessile,  broadly  linear  or  linear-spatulate, 
narrow  at  base,  rounded  to  the  obtuse  summit,  0.5  to  2.0  cm.  long,  0.2  to  0.5  cm.  wide, 
strictly  entire,  densely  and  permanently  white-furfuraceous;  flowers  dioecious  or  some- 
times monoecious,  the  staminate  in  large  glomerules  along  nearly  naked  terminal  spikes, 
the  pistillate  in  elongated  terminal  spikes  which  far  overtop  the  leafy  stems;  perianth 
5-cleft  in  the  staminate  flowers,  wanting  in  the  pistillate;  fruiting  bracts  sessile  or  sub- 
sessile,  thick,  scarcely  spongious,  united  nearly  to  summit,  narrowly  fan-shaped,  the 
terminal  free  portion  very  broad  and  obtuse,  4  to  6  mm.  long,  3  to  4  mm.  wide,  the 
sides  with  thick  wart-like  or  somewhat  flattened  appendages;  seed  about  2  mm.  long, 
reddish-brown;  radicle  superior. 

Alkaline  plains  of  western  Colorado,  southern  Utah,  and  northern  New  Mexico. 
Tjrpe  locaUty,  Grand  Junction,  Colorado.  Collections:  Type  collection.  May,  1891, 
Eastwood  (Gr,  UC,  US);  Colorado:  mesa  southeast  of  Grand  Junction,  Hall  1104-9  (UC); 
Whitewater,  Hall  11050  (UC);  San  Juan  Plains,  Brandegee  1086,  in  part  (UC);  between 
Hotchkiss  and  Crawford,  Cowen  1118  (Gr);  Mesa  Grande,  on  the  Gunnison  River, 
Purpus  334  (UC);  Solitude,  Utah,  Coville  and  Kearney  2603  (US);  Desert  Station, 
Utah,  Rydherg  and  Garrett  831 4  (NY,  US);  Emery,  Utah,  Jones  5444  (NY,  UC,  US); 
south  of  Green  River,  Utah,  Hall  11038  (UC);  mesas  south  of  San  Juan  River,  5  km. 
south  of  Shiprock  Station,  New  Mexico,  September  22,  1920,  Hall  (CI). 

SYNONYM. 

Atriplex  nuttalli  corrugata  Nelson,  in  Coulter  and  Nelson,  Man.  Rocky  Mt.  Bot.  168,  1909. — No 
reasons  were  given  for  this  reduction  to  a  species  which  differs  in  several  fundamental  features,  as  will  be 
indicated  beyond. 

RELATIONSHIPS. 

Atriplex  corrugata  does  not  closely  approach  any  other  species  in  its  characters.  It 
is  commonly  placed  next  to  A.  nuttalli  in  taxonomic  treatments,  perhaps  because  the 
two  are  somewhat  similar  in  superficial  appearance  and  occupy  the  same  habitat. 
Where  they  grow  together,  corrugata  may  be  recognized  at  a  glance,  for  its  lower,  more 
compact,  and  mat-like  habit  and  the  small  crowded  leaves  give  to  the  plant  a  more 
delicate  aspect.  Its  technical  characters  indicate  a  considerable  phylogenetic  divergence. 
Especially  notable  are  the  opposite  position  of  the  leaves  and  the  shape  of  the  fruiting 
bracts,  which  are  relatively  much  broader  above  and  have  the  free  terminal  portion 
developed  into  a  broad,  smooth,  essentially  entire,  lip-like  appendage.  The  opposite 
leaves  suggest  a  possible  connection  with  some  group  more  primitive  than  the  Nut- 
tallianae,  for  example,  the  opposite-leaved  A.  decumbens  or  A.  matamorensis.  The 
flowers  are  occasionally  monoecious  at  the  type  locality.  Miss  Eastwood  has  here 
collected  specimens,  some  of  which  are  purely  staminate,  some  purely  pistillate,  and 
others  with  several  of  the  lower  clusters  in  each  spike  pistillate,  the  remainder  of  the 
spike  staminate  (Grand  Junction,  May,  1892,  Eastwood,  UC). 

ECOLOGY  AND  USES. 

Atriplex  corrugata  resembles  A.  nuttalli  closely  in  its  ecological  behavior,  evidently 
having  sprung  from  it  as  an  adaptation  to  greater  drought  arising  from  increased  salt- 
content.  They  occur  together  throughout  the  range  of  the  former,  sometimes  mixing 
on  apparently  equal  terms,  but  with  corrugata  regularly  taking  the  more  halophytic 
depressions  and  ridges.     It  is  especially  typical  of  the  most  sahne  bad-land  ridges, 


A.    CORRUGATA — A.    POLYCARPA.  331 

and  sometimes  pushes  as  far  into  white-alkali  flats  as  does  Suaeda.    It  forms  low  mounds 
in  the  manner  of  nuttalli,  but  these  are  smaller,  owing  to  its  more  appressed  habit. 

This  species  is  looked  upon  with  disfavor  by  the  stockmen  of  Utah,  who  call  it  "poison 
clover."  It  is  browsed  to  a  considerable  extent  by  sheep,  especially  after  other  forage 
has  been  used  up,  with  the  result  that  many  of  the  animals  are  fatally  poisoned.  While 
this  has  not  been  corroborated  by  carefully  controlled  feeding  experiments,  the  range 
evidence  comes  from  trustworthy  sources.  It  is  probable  that  the  poisoning  is  due  to 
saponin,  as  seems  to  be  the  case  with  A.  canescens.  The  only  other  browse  on  the  range 
at  the  time  of  greatest  injury  is  A.  nuttalli,  which  is  much  less  if  at  all  injurious. 

40.  ATRIPLEX  POLYCARPA  (Torrey)  Watson,  Proc.  Am.  Acad.  9:117,  1874.     Plate  52. 
Allscale. 

Erect  shrub,  woody  throughout,  intricately  much  branched  to  form  twiggy  and 
usually  rounded  plants  8  to  20  dm.  high  (seedlings  sometimes  fruit  abundantly  when 
only  3  dm.  high);  branches  not  angled,  at  first  gray-scurfy,  later  smooth  and  light  or 
yellowish  brown,  the  old  bark  dark  and  breaking  longitudinally;  leaves  crowded  on  the 
young  twigs,  early  deciduous,  alternate,  usually  sessile,  elliptic-oblong  or  spatulate, 
narrowed  at  base,  acutish  or  obtuse  at  apex,  usually  0.3  to  1.5  cm.  long  and  0.2  to  0.4 
cm.  wide,  but  up  to  2.5  cm.  long  on  sterile  twigs,  often  with  very  small  leaves  fascicled 
in  the  axils,  entire,  thickish,  gray  with  a  dense  permanent  scurf,  l-nerved;  flowers 
dioecious,  the  staminate  glomerules  in  axillary  and  terminal  spikes,  the  pistillate  crowded 
along  the  numerous  divergent  branches  of  profuse  terminal  panicles;  perianth  5-cleft 
in  staminate  flowers,  wanting  in  the  pistillate;  fruiting  bracts  sessile,  moderately  or 
scarcely  compressed  (the  margins  sometimes  broad  and  flat),  united  to  well  above  the 
middle  or  rarely  distinct  nearly  to  the  base,  cuneate-orbicular,  2  to  4  mm.  long  or  up 
to  6  mm.  when  the  teeth  are  well  developed,  as  broad  or  broader,  the  thin  margins 
shallowly  to  deeply  and  laciniately  dentate  above  the  base,  the  faces  copiously  cristate- 
appendaged  to  tuberculate  or  smooth;  seed  1  to  1.5  mm.  long,  pale  brown;  radicle 
superior.     {Obione  polycarpa  Torrey,  Pacif.  R.  R.  Rep.  4:130,  1857.) 

Desert  areas  from  southern  Nevada,  southern  Utah,  Arizona,  and  Sonora  west  across 
Lower  California,  north  to  the  San  Joaquin  and  Owens  Valleys,  California;  abundant 
on  the  Colorado  Desert  of  western  Arizona  and  eastern  California,  also  in  the  south 
and  west  portions  of  the  San  Joaquin  Valley,  California.  Type  locality,  Valley  of  the 
Gila  River,  Arizona.  Collections:  13  km.  above  Rioville,  Nevada,  April  11,  12,  and  13, 
1894,  Jones  (US);  St.  George,  Utah,  Jones  (Herb.  Jones);  type  collection,  October  28, 
1846;  Emory  (NY);  Arizona:  Tempe,  Kearney  89,  119  (US);  Maricopa,  September  3, 
1901,  Thornber  (UC);  Mellen,  along  the  Colorado  River,  February  25,  1910,  Grinnell 
(UC);  Yuma,  Hall  11209  (UC);  near  Tucson,  Thornber  109a  (NY,  UC,  US);  Sonoyta, 
Sonora,  Mearns  2732  (US);  San  Francisquito  Bay,  Gulf  of  California,  Rose  16754  (NY, 
US);  Puerto  Refugio,  Angel  de  la  Guardia  Island,  Gulf  of  California,  Johnston  3368 
(SF,  UC);  Lower  Cahfornia:  Comondu,  April  24,  1889,  Brandegee  (UC,  type  of  A. 
curvidens  Brandegee,  minor  variation  3);  Point  Abreojos,  Rose  16254  (US);  San  Bar- 
tolome  Bay,  April  12,  1897,  Brandegee  (UC);  Rosalia  Bay,  Anthony  ISO  (UC,  US); 
California:  Borregos  Springs,  Colorado  Desert,  April  18,  1895,  Brandegee  (UC);  Palm 
Springs  and  southward,  Schellenger  34  (UC);  Indio,  Kearney  8  (US);  Mecca,  Parish 
8262  (Gr);  Dry  Lake  near  Rosamond,  western  end  of  Mojave  Desert,  Hall  10969;  west 
side  of  Tehachapi  Pass,  Hall  10966,  10967,  10968  (UC);  Bakersfield,  September  28, 
1894,  Eastwood  (UC);  near  Kern  Lake,  Davy  2137  (UC);  near  Lost  Hills,  western  Kern 
County,  Hall  11774,  11775  (UC);  Shandon,  San  Luis  Obispo  County,  Severin  (CI); 
between  Mendota  and  Coalinga,  Fresno  County,  Hall  11763  (UC);  Wildcat  Canon, 
western  Merced  County,  Severin  (CI);  sandy  plains  of  Owens  Valley,  Purpus  3043 


332  GENUS   ATRIPLEX. 

(UC);  near  Bennett  Wells,  Death  Valley,  Coville  and  Funston  196  (US);  additional 
localities  mentioned  by  Merriam  (N.  Am.  Fauna  7:325,  1893)  include  Lone  Pine  to 
Haway  Meadows  in  Owens  Valley,  California,  and  the  following,  all  in  Nevada:  Grape- 
vine Canon,  Oasis  Valley,  south  of  Pahranagat  Lake,  Virgin  and  Lower  Muddy  Valleys, 
and  east  of  Pahrump  Valley. 

MINOR  VARIATIONS  AND  SYNONYMS. 

1. — Variation  in  the  sculpturing  and  dentation  of  the  bracts,  to  be  expected  in  most  species  of  Atriplex,  is 
here  very  marked.  These  variations  often  occur  in  varying  degrees  on  neighboring  plants.  But  at  one  locality 
in  the  Tehachapi  Pass,  California,  certain  individual  plants  have  only  smooth  or  nearly  smooth  bracts;  other 
plants  close  by  have  only  bracts  in  which  the  faces  are  covered  with  tubercles  and  cristate  appendages;  still 
others  have  the  two  kinds  of  bracts  in  about  equal  proportions.  This  last-mentioned  form  appears  to  be  a 
hybrid  between  the  other  two,  which,  if  this  is  the  case,  should  be  considered  as  genetic  races.  Samples  of 
the  plants  are  filed  at  the  Herbarium  of  the  University  of  California  (Nos.  205322,  20532-3,  205331,  respectively). 

2.— A  form  with  exceptionally  small,  ovate  leaves  has  been  collected  at  Maricopa,  Arizona  (September  3, 
1901,  Thornber,  UC,  Nos.  7195,  7196).  In  many  other  collections  there  occur  simDar  leaves  but  only  fascicled 
in  the  axils  of  longer  normal  ones.  In  the  Maricopa  plants  even  a  portion  of  the  primary  leaves  are  ovate, 
closely  sessile  by  a  subcordate  base,  and  only  about  4  mm.  long.  They  suggest  the  sagittate-sessile  leaves  of 
A.  julacea.     (See  plate  52.) 

3.  Atriplex  curvidens  Brandegee,  Proc.  Calif.  Acad.  Sci.  II,  2:  201,  1889. — An  extreme  form  as  to  the 
fruiting  bracts,  which  are  broadly  obovate  with  a  cuneate  base,  broader  than  long,  mostly  not  appendaged, 
and  with  remarkably  broad,  thin  margins  which  are  cleft  into  numerous  linear  often  curved  segments.  Type, 
Comondu,  Lower  California,  April  24,  1889,  Brandegee  (UC);  known  also  from  San  Esteban  Island,  Gulf  of 
California,  Johnston  SI 98  (SF,  UC).  Intermediate  forms  in  which  the  bracts  are  of  the  same  shape  and  size 
but  with  shorter  and  thicker  marginal  teeth  have  been  collected  near  Tucson,  Arizona  (October  16,  1901, 
Thornber,  UC).  It  has  been  suggested  by  Standley  (Bull.  Torr.  Club  44:  424,  1917)  that  the  type  specimen 
may  be  abnormal  as  the  result  of  a  fungus  which  grew  upon  it. 

4.  Obione  polycarpa  Torrey,  Pacif.  R.  R.  Rep.  4:130,  1857. — The  original  publication  of  the  species, 
although  the  same  name  appeared  earlier  without  a  description  (Torrey  in  Emory,  Notes  Mil.  Rec.  150,  1848). 

RELATIONSHIPS. 

The  relationships  of  this  species  are  with  A.  julacea  and  A.  barclayana,  as  has  been 
more  fully  indicated  under  the  former.  The  fruiting  bracts  tend  to  the  obovate  rather 
than  to  the  ovate  shape  characteristic  of  julacea  and  the  leaves  are  never  truly  sagittate- 
clasping  as  in  that.  But  on  occasional  plants  some  of  the  leaves  are  ovate-cordate  and 
closely  sessile,  as  described  under  minor  variation  2.  Such  specimens  suggest  a  former 
connection  between  the  two. 

ECOLOGY. 

Atriplex  polycarpa  forms  characteristic  consocies  in  alkaline  basins  in  the  Southwest. 
In  the  region  of  lentiformis  it  lies  above  the  latter  on  better-drained  soil,  making  the  next 
stage  in  the  succession,  the  two  mingling  through  a  considerable  ecotone.  Beyond  the 
range  of  this  it  is  the  chief  dominant  of  strongly  alkaline  valleys,  often  associated  with 
Suaeda  and  sometimes  zoned  about  it.  In  the  Santa  Cruz  and  Gila  Valleys  of  southern 
Arizona  it  may  form  the  center  within  a  zone  of  A.  canescens,  or  the  two  may  mix  over 
considerable  areas.  It  is  often  associated  with  Prosopis  and  Larrea,  and  may  extend 
up  rocky  slopes  to  mix  with  Parkinsonia,  Fouquiera,  and  Cereus.  In  the  Antelope 
Valley  of  California  it  grows  with  A.  confertifolia  in  the  Larrea  community.  It  is  nearly 
as  tolerant  of  alkali  as  lentiformis,  Kearney  finding  a  salt-content  of  3.12  per  cent  for 
the  first  foot,  2.18  for  the  second  foot,  and  0.69  for  the  third. 

USES. 

The  allscale,  also  called  cattle  spinach,  probably  equals  A.  canescens  in  its  value  as 

a  browse  plant,  practically  always  assuming  a  low  compact  form  wherever  cattle  and 

sheep  are  present.     Its  value  is  high,  owing  to  its  usual  association  with  a  number  of 

unpalatable  species.    In  some  districts,  such  as  the  westerly  slopes  of  the  San  Joaquin 


A.    JULACEA — ^A.    HTMENELYTRA.  333 

Valley,  California,  where  it  occupies  extensive  areas  too  hot  and  arid  for  other  shrubs, 
it  serves  as  browse  for  large  numbers  of  sheep  while  these  are  being  moved  from  one 
range  to  another.  In  such  places,  where  all  feed  is  at  a  premium,  the  shrubs  are  often 
stripped  of  their  scant  foliage  and  many  plants  finally  die  as  a  result  of  repeated  browsing. 
In  some  portions  of  the  Lost  Hills  district  over  50  per  cent  of  the  plants  have  been  killed, 
presumably  because  of  this.  Atriplex  poly  car  pa  is  regarded  by  Severin  as  the  most 
important  of  the  shrubby  food-plants  of  Eutettix.  Like  most  species  of  the  genus,  it 
may  be  an  occasional  cause  of  hay-fever. 

41.  ATRIPLEX  JULACEA  Watson,  Proc.  Am.  Acad.  20:370,  1885.     Plate  52. 

Procumbent  subshrub  with  ascending  or  erect  crowded  slender  twigs,  these  only 
slightly  woody;  branches  (2  to  6  dm.  long)  slender,  not  angled,  gray-scurfy  or  glabrate, 
the  bark  thick  brown  and  corky  on  old  basal  portions;  leaves  crowded  and  sometimes 
imbricate  on  the  branchlets,  alternate,  closely  sessile  by  a  sagittate-clasping  base, 
ovate-triangular,  usually  sulcate  by  the  folding  back  of  the  margins,  obtuse  at  apex, 
0.2  to  0.4  cm.  long,  0.1  to  0.2  cm.  wide,  entire,  thick,  gray  with  a  dense  permanent 
scurf,  l-nerved;  flowers  dioecious,  solitary  or  in  few-flowered  axillary  glomerules;  perianth 
cleft  in  the  staminate  flowers,  wanting  in  the  pistillate;  fruiting  bracts  sessile,  not  com- 
pressed, united  to  above  the  middle,  ovate,  4  to  6  mm.  long,  about  as  broad,  the  surface 
covered  with  irregular  corky  appendages;  seed  about  1  mm.  long,  reddish-brown ; radicle 
superior. 

Pacific  Coast  of  Lower  California  from  near  the  northern  boundary  to  San  Gregorio. 
Type  locaHty,  Todos  Santos  Bay.  Collections,  all  from  Lower  California:  Type  col- 
lection, September  30,  1884,  Orcutt  (Or);  Todos  Santos  Island,  March  9,  1897,  Brandegee 
(UC);  Ensenada,  Jones  3737  (NY,  US);  Sauzal,  April  11,  1885,  Orcutt  (Gr,  US);  Cape 
San  Quentin,  May  10,  1885,  Greene  (DS,  US);  San  Quentin  Bay,  Palmer  726  (Gr,  NY, 
US);  San  Telmo,  May  31,  1893,  Brandegee  (UC);  Socorro,  May,  1889,  Brandegee  (UC); 
Natividad  Island,  Anthony  365  (DS,  UC);  San  Bartolome  Bay,  April  12,  1897,  Brandegee 
(UC);  Point  Abreojos,  Rose  16252  (US);  San  Gregorio,  April  6,  1889,  Brandegee  (UC). 

RELATIONSHIPS. 

Watson's  statement  following  the  original  description  that  this  species  is  related  to 
A .  polycarpa  is  borne  out  by  all  of  the  evidence  assembled  from  more  recent  collections. 
It  is  less  woody  than  that  and  therefore  seems  to  stand  between  it  and  the  subshrubby 
Atriplexes  hke  A.  barclayana.  But  it  is  more  woody  than  descriptions  lead  one  to  believe. 
Sometimes  the  hard  stems  are  3  mm.  thick  and  some  herbarium  specimens  indicate 
that  the  principal  stems  are  sometimes  erect  from  a  very  short  spreading  base  {Anthony 
365).  Such  specimens  look  very  much  like  young  plants  of  A.  polycarpa.  A.  julacea 
is  well  set  off  from  all  other  species  by  the  minute  and  sagittate-clasping  leaves. 
ECOLOGY  AND  USES. 

Nothing  is  known  regarding  the  ecology  of  this  plant,  aside  from  the  fact  that  it 
forms  low,  tangled  masses  in  the  proximity  of  the  sea.    It  has  no  uses  as  far  as  known. 

42.  ATRIPLEX  HYMENELYTR A  (Torrey)  Watson,  Proc.  Am.  Acad.  9:119,  1874. 
Plate  53.     Hollyscale;  Desert  Holly. 

Erect  compactly  branched  shrub,  woody  throughout,  of  rounded  outline  when  normally 
developed,  3  to  10  dm.  high  and  broad;  branches  not  striate,  white  with  a  dense  and  long- 
persisting  scurf;  the  bark  rough  and  gray  on  old  basal  portions;  leaves  numerous,  per- 
sistent, alternate,  on  petioles  5  to  10  mm.  long,  orbicular  or  round-ovate,  truncate 
subcordate  or  short-cuneate  at  the  base,  obtuse  at  apex,  the  blade  1.5  to  3  cm.  long  and 
about  as  wide,  deeply  and  irregularly  dentate  with  salient  sharp  teeth,  thick,  silvery- 


334  GENUS   ATRIPLEX. 

white  with  a  dense,  smooth,  persistent  scurf,  l-nerved  from  the  base;  flowers  dioecious, 
in  short  dense  leafy  panicles  and  short  axillary  spikes,  or  the  pistillate  inflorescence 
sometimes  more  open  and  less  leafy ;  perianth  5-parted  in  the  staminate  flowers,  wanting 
in  the  pistillate;  fruiting  bracts  borne  on  a  short  fusiform  or  turbinate  stalk,  strongly 
compressed,  except  for  the  small  convex  body,  distinct  or  nearly  so,  orbicular  or  round- 
reniform,  6  to  12  mm.  long  and  about  as  broad,  the  margins  entire,  the  faces  smooth 
but  reticulate-veiny;  seed  about  2  mm.  long,  brown;  radicle  superior.  {Obione  hymen- 
elytra  Torrey,  Pacif.  R.  Rep.  4:129,  plate  20,  1857.) 

Alkaline  deserts  of  southeastern  California,  southern  Nevada,  and  southwestern 
Utah,  south  across  western  Arizona  to  Sonora  and  Lower  California.  Type  locality, 
hills  and  gravelly  places  on  Williams  River,  Arizona.  Collections:  California:  West 
from  Bennett  Wells,  Death  Valley,  Coville  and  Funston  195  (Gr,  US);  near  Fremonts 
Peak,  Mojave  Desert,  Hall  and  Chandler  6855  (UC);  near  Barstow,  Mojave  Desert, 
Rose  12060  (US);  Borregos  Springs,  Carisso  Creek,  and  Split  Mountain,  all  on  the 
Colorado  Desert,  Brandegee  (UC);  Coachella,  Colorado  Desert,  April,  1905,  Greata 
(UC);  Signal  Mountain,  Colorado  Desert,  December  29,  1907,  Abrams  (Gr);  west  of 
Logan,  Clark  County,  Nevada,,  Heller  10453  (DS,  Gr,  NY,  US) ;  southern  Utah,  Palmer, 
1870,  ace.  Bot.  King;  gravelly  mesa  near  Mellen,  Arizona,  February  25,  1910,  Grinnell 
(UC);  Bill  Williams  Fork,  Arizona,  Bigelow  (Gr);  Mohawk  Station,  lower  Gila  River, 
Arizona,  Greene  1089  (Gr);  Gila,  Sonora,  Thurber  (Gr);  Cucopa  Mountains,  Lower 
California,  MacDougal  I4S  (NY);  Los  Angeles  Bay,  Lower  California,  Johnston  344^ 
(SF,  UC).  Additional  localities  in  California  and  Nevada  are  listed  by  Coville  (Contr. 
U.  S.  Nat.  Herb.  4:180,  1893). 

RELATIONSHIPS. 

This  is  one  of  the  most  distinct  of  the  American  species  of  Atriplex.  It  is  unlike  any 
other  in  its  roundish,  deeply  dentate  leaves  and  in  its  large,  orbicular,  thin-winged 
bracts.  The  development  of  a  wing  from  the  upper  portion  of  the  bract,  the  position  of 
the  seed,  and  the  short  stipe-like  base  to  the  bracts,  all  suggest  A.  confertifolia,  but  the 
body  of  the  bract  is  not  indurated  as  in  that,  and  otherwise  these  two  species  are  quite 
unlike. 

ECOLOGY  AND  USES. 

Atriplex  hymenelytra  practically  never  forms  a  dominant  community,  but  grows 
sparsely  or  copiously  in  association  with  the  dominants  of  dry  rocky  slopes  about  valleys 
in  which  polycarpa  or  lentiformis  is  usually  found.  Its  usual  associates  are  Encelia, 
Franseria,  Larrea,  Fouquiera,  Opuntia,  etc.  The  flowering  period  is  earlier  than  that  of 
any  other  species,  the  staminate  flowers  opening  from  February  to  April. 

The  plants  are  normal  and  symmetrical,  and  show  no  evidence  of  being  browsed. 
Their  silvery,  spiny  leaves  and  symmetry  make  them  in  demand  for  decoration,  and 
carloads  are  shipped  East,  especially  at  Christmas  time. 

43.  ATRIPLEX  LENTIFORMIS  (Torrey)  Watson,  Proc.  Am.  Acad.  9:118,  1874. 
Plates  54  and  55.     Lenscale. 

Erect  shrub,  woody  throughout,  either  rigidly  or  flexuously  much  branched,  globoid 
or  dome-shaped  in  outline  when  well  developed,  10  to  30  dm.  high  and  with  a  spread 
of  1  to  50  dm ;  branches  either  terete  or  sharply  angled,  gray-scurfy  at  first,  soon  smooth 
and  pale,  the  bark  rough  and  gray  on  old  trunks;  leaves  numerous,  deciduous  in  desert 
forms  and  the  branchlets  then  spiny,  alternate,  petioled  or  the  upper  ones  sessile,  deltoid 
or  rhombic  to  ovate  or  oblong  (nearly  orbicular  in  minor  variation  4),  truncate  to  cuneate 
at  base,  obtuse  and  short-mucronate  at  apex,  1  to  5  cm.  long,  0.5  to  5  cm.  wide,  entire  or 
subhastate,  rather  thin,  gray  or  bluish  with  a  fine,  close  permanent  scurf,  l-nerved  from 
the  base;  flowers  dioecious  or  monoecious,  both  staminate  and  pistillate  crowded  along 


A.    LENTIFORMI8.  335 

the  branches  of  profuse  terminal  panicles,  the  fruiting  branches  sometimes  curved 
downward  by  the  weight  of  their  load;  perianth  4-  or  5-cleft  in  the  staminate  flowers, 
wanting  in  the  pistillate;  fruiting  bracts  sessile,  moderately  compressed,  united  only 
near  the  base  or  up  to  the  middle,  orbicular  or  slightly  broader  than  long  or  rarely  broad- 
elliptic,  2  to  5  or  7  mm.  long  and  broad,  the  free  margins  entire  or  crenulate,  the  faces 
smooth;  seed  1.2  to  1.5  mm.  long,  brown;  radicle  superior.  (Obione  leniiformis  Torrey 
in  Sitgreaves  Rep.  Exp.  169,  1853.) 

Southern  half  of  California,  both  on  the  coast  and  inland,  to  Nevada,  southwestern 
Utah,  New  Mexico,  Sonora,  and  the  border  of  Lower  California. 

SUBSPECIES. 

The  forms  of  Atriplex  lentiformis  may  be  assembled  into  four  subspecies.  Each 
inhabits  a  different  geographic  area  although  typica  and  torreyi  closely  approach  each 
other  in  eastern  California.  Subspecies  typica  is  central,  both  geographically  and  phylo- 
genetically,  but  since  the  others  probably  were  derived  from  it,  this  form  is  given  first 
place  in  the  sequence. 

Key  to  the  Subspecies  of  Atriplex  lentiformis. 
Twigs  not  sharply  angled. 

Mature  bracts  mostly  crenulate  on  the  margins,  2.5  to  4  or  rarely  5  mm.  broad;  leavea 

mostly  1  to  2.5  cm.  wide.     Interior (a)  typica  (p.  335). 

Mature  bracts  mostly  entire,  3.5  to  5  or  rarely  7  mm.  broad;  leaves  mostly  1.5  to  5  cm. 

wide.     Coastal (6)  breweri  (p.  335). 

Twigs  sharply  angled  by  several  raised  rib-like  longitudinal  striae. 

Mature  bracts  orbicular;  leaves  deltoid  to  ovate,  rarely  oblong (c)   torreyi  (p.  336). 

Mature  bracts  broader  than  long;  leaves  narrowly  ovate  to  narrowly  oblong (d)  griffithsi  (p.  336). 

43a.  Atriplex  lentiformis  typica. — Branches  and  twigs  terete  or  with  only  obtuse 
and  irregular  angles,  often  rigid,  rarely  becoming  spiny;  leaf-blades  usually  2  to  4  cm. 
long,  1  to  2.5  cm.  wide;  flowers  mostly  dioecious  but  some  plants  with  both  sexes;  mature 
bracts  flattish  or  only  slightly  convex,  mostly  2.5  to  4  mm.  in  diameter,  or  up  to  5  mm. 
and  spongy-thickened  when  borne  with  staminate  flowers,  the  margins  minutely  crenulate 
or  rarely  entire.  {Obione  lentiformis  Torrey  in  Sitgreaves,  Rep.  Exp.  169,  1853.)  Sali- 
nas and  San  Joaquin  Valleys,  California,  to  southwestern  Utah;  southward  in  the  inte- 
rior to  Lower  California  and  Sonora.  Type  locality,  "on  the  Colorado  of  California." 
Collections:  California:  Firebaugh,  northwestern  Fresno  County,  Hall  11760  (UC); 
2.5  km.  west  of  Coalinga,  Fresno  County, //aZi  11765  (UC);  8  km.  south  of  King  City, 
Salinas  Valley,  October  11,  1918,  Severin  (UC,  pocket),  Bakersfield,  September  24, 
1894,  Eastwood  (Gr,  UC);  Kern  Lake,  Davy  2911  (UC);  Resting  Springs  Valley,  Inyo 
County,  Coville  and  Funston  264  (US);  near  Saratoga  Springs,  Death  Valley,  Coville 
and  Funston  SOS  (US);  type  collection,  Sitgreaves  Expedition,  November,  1851  (Gr); 
southwestern  part  of  Colorado  Desert,  Orcutt  2083,  2084  (US);  between  Coachella 
and  Wolters,  Colorado  Desert,  Schellenger  54  (UC);  Salton  Crossing,  Colorado  Desert, 
April  3,  1901,  Brandegee  (UC);  St.  Joe,  Nevada,  Jones  5030k  (US);  Colorado  River, 
Arizona,  opposite  Needles,  March  3,  1910,  Grinnell  (UC);  Chemehuevis  Valley,  Arizona, 
Jepson  5197  (DS);  Yuma,  Arizona,  Hall  11208  (UC);  Tempe,  Arizona,  September  1, 
1901,  Thornber  (UC,  US);  Gardners  Lagoon,  Lower  California,  Schoenfeldt  2913  (US); 
20  km.  north  of  Lerdo,  Sonora,  December  2,  1898,  Price  (DS);  Altar  River,  Sonora, 
August  25,  1884,  Pringle  (Gr,  NY,  US).  Additional  stations,  some  of  which  may  be 
for  subspecies  torreyi,  include  the  following,  according  to  Merriam  (N.  Am.  Fauna  7: 
327,  1893):  Oasis,  Pahranagat,  Virgin,  and  Lower  Muddy  Valleys,  all  in  Nevada; 
Amargosa  Canon  and  North  of  Willow  Spring,  Antelope  Valley,  California;  and  Santa 
Clara  Valley,  Utah. 

436.  Atriplex  lentiformis  breweri  (Watson).  Branches  and  twigs  terete  or  with 
only  obtuse  and  irregular  angles,  not  becoming  spiny;  leaf-blades  usually  3  to  5  cm. 


336  GENUS   ATRIPLEX. 

long,  1.5  to  5  cm.  wide;  flowers  either  dioecious  or  monoecious;  mature  bracts  flattish 
or  convex,  mostly  3.5  to  5  mm.  in  diameter  or  up  to  7  mm.  when  borne  in  staminate 
inflorescences,  commonly  thicker  than  in  other  forms,  the  margins  usually  entire  or 
only  obscurely  undulate.  {A.  breweri  Watson,  Proc.  Am.  Acad.  9:119,  1874.)  Coast  of 
California  from  Suisun,  San  Francisco  Bay,  to  Orange  County.  Type  locality,  Santa 
Monica,  California.  Collections,  all  from  California:  Railroad  embankment  near  Teal, 
Suisun  Marshes,  October  15,  1905,  Dudley  (DS);  sandy  creek  bottoms  south  of  HoUister, 
San  Benito  County,  October  15,  1919,  Hall  (UC)  ;•  ocean  bluffs,  near  Santa  Barbara, 
Eastwood  209  (NY,  UC,  US,  monoecious  in  part,  therefore  minor  variation  5,  A.  orbicu- 
laris Watson);  Santa  Cruz  Island,  Francheschi  (UC);  river-bottoms,  Santa  Maria, 
October  17,  1919,  Hall  (CI);  Ventura,  October  18,  1919,  Hall  (UC,  most  of  the  plants 
monoecious,  therefore  minor  variation  5,  A.  orbicularis  Watson);  type  collection,  "on 
banks  of  seashore,  Santa  Monica,"  Brewer  75  (Or,  UC,  US);  base  of  bluffs,  seashore, 
Santa  Monica,  Parish  1126  (Gr,  type  of  A.  orbicularis  Watson,  minor  variation  5); 
Ballona,  Los  Angeles  County,  Braunton  710  (UC,  US);  Avalon,  Santa  Catalina  Island, 
only  one  plant  seen,  June,  1898,  Trask  (US);  San  Clemente  Island,  Trask  19  (US); 
San  Juan  Capistrano,  Orange  County,  June,  1896,  McClatchie  (UC). 

43c.  Atriplex  lentiformis  torreyi  (Watson).— Branches  and  twigs  acutely  angled 
by  prominent  striae,  becoming  somewhat  spiny  as  the  leaves  and  bracts  are  lost;  leaf- 
blades  mostly  1.5  to  3  cm.  long,  0.5  to  2  cm.  wide;  flowers  dioecious;  mature  bracts 
flattish  or  somewhat  convex,  2  to  4  mm.  in  diameter,  the  margins  minutely  crenulate. 
(Obione  torreyi  Watson,  Bot.  King's  Expl.  290,  1871.)  Principally  in  Nevada,  extend- 
ing southwest  to  the  Mojave  Desert,  California,  and  east  into  southwestern  Utah. 
Type  locaUty,  dry  valleys  bordering  the  Truckee  and  Carson  Rivers,  Nevada.  Col- 
lections, all  from  Nevada,  except  as  otherwise  indicated:  Gerlach,  northern  Washoe 
County,  Hall  11792  (UC);  Reese  River  Valley,  Warren  (DS);  type  collection,  Humboldt 
County,  1865,  Torrey  463  (Gr,  NY);  Carson  Desert,  Watson  984  (Gr,  NY);  Truckee 
Canon,  below  Vista,  Hall  11230  (UC);  Smoke  Creek,  Griffiths  and  Hunter  511  (NY); 
Las  Vegas,  Hall  10801  (UC) ;  alkaline  plain  near  Dry  Lake,  Antelope  Valley,  California, 
Davy  2945;  Barstow,  California,  Jepson  5174  (DS);  Lone  Pine,  California  (according  to 
Jepson,  Fl.  Calif.  440,  1914);  St.  George,  Utah,  Jones  6094  (NY,  UC). 

43d.  Atriplex  lentiformis  griffithsi  (Standley). — Branches  and  twigs  acutely 
angled  by  prominent  striae,  perhaps  becoming  spiny  in  age;  leaf-blades  (as  far  as  known) 
1  to  2.5  cm.  long,  0.3  to  1  cm.  wide  (elliptic-ovate  to  narrowly  oblong);  flowers  dioecious; 
mature  bracts  nearly  flat  but  slightly  convex,  4  to  6  mm.  broad  (4  to  5  mm.  long,  thus 
broader  than  long),  the  margins  minutely  crenulate  or  some  entire.  (A.  griffithsi 
Standley,  N.  Am.  Fl.  21 :63,  1916.)  Known  only  from  the  vicinity  of  the  type  locahty, 
Willcox,  southeastern  Arizona.  Collections:  Type  collection,  Griffiths  1895  (NY); 
Willcox  Flat,  Arizona,  Shreve  4239  (UC). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Atriplex  breweri  Watson,  Proc.  Am.  Acad.  9:  119,  1874.— yl.  lentiformis  breweri. 

2.  A.  GRIFFITHSI  Standley,  N.  Am.  Fl.  21:  63,  1916.—^.  lentiformis  griffithsi. 

3.  A.  LENTIFORMIS  Watson,  1.  c,  118,  1874. — Based  upon  Obione  lentiformis,  which  see. 

4.  A.  LENTIFORMIS  BREWERI  (Watson). — A  form  with  spatulate-orbicular  entire  to  dentate  leaves  1.5  to  3 
cm.  broad  and  bracts  9  to  10  mm.  broad  has  been  collected  on  the  seacoast  bluffs  at  Playa  del  Rey.  Los  Angeles 
County,  California  (Parish  11S71,  UC).  With  only  an  occasional  exception,  the  ovaries  fail  to  develop  and 
the  whole  appearance  of  the  plant  is  that  of  a  monstrosity.  There  is  no  evidence  of  injury  due  to  insects. 
Staminate  plants  from  the  same  locality  (Johnston  1900,  UC)  have  similarly  broad  suborbicular  leaves,  some 
of  which  are  truncate  at  base,  the  remainder  tapering  to  the  petiole.  The  leaf-shape  is  approached  in  speci- 
mens of  subspecies  typica  from  the  Colorado  River  bottoms  near  Needles  (March  3,  1910,  Grinnell,  UC). 
According  to  Johnston,  there  is  a  considerable  area  at  Playa  del  Rcy  where  the  peculiar  form  grows  to  the  ex- 
clusion of  normal  breweri.    The  latter,  however,  grows  along  near-by  lagoons. 


A.    LENTIFORMIS.  337 

5.  A.  ORBICULARIS  Watson,  1.  c,  17:377,  1882. — The  monoecious  state  of  A.  kntiformis  breweri,  "the 
small  dense  staminate  clusters  with  the  pistillate  flowers  and  in  slender  terminal  raoniliform  spikes."  Watson 
did  not  compare  his  proposed  species  with  any  member  of  the  lenliformis  group,  but  Parish,  the  collector  of 
the  type  specimen,  has  reduced  it  to  breweri,  and  has  given  ample  reason  for  so  doing  (Erythea  7:  91,  1899). 
Still  later  studies  along  the  coast  of  southern  California,  especially  in  Ventura  County,  confirm  Parish's  con- 
clusion. Nearly  all  stages  in  the  separation  of  the  sexes  are  found.  Some  plants  are  about  equally  male  and 
female,  others  in  the  same  environment  and  not  distinguishable  by  other  characters  vary  to  purely  pistillate 
and  to  purely  staminate.  Very  few  plants  of  either  sex  fail  to  reveal  at  least  a  few  flowers  of  the  other  sort 
on  careful  examination.     Santa  Monica  is  the  type  locality  for  both  breweri  and  orbicidaris. 

6.  A.  TORREYi  Watson,  1.  c,  9:  119,  1874. — A.  lenliformis  torreyi. 

7.  Obione  LENTIFORMIS  Torrey,  in  Sitgreaves,  Rep.  Exp.  169,  1853. — A.  lenliformis  lypica. 

8.  O.  TORREYI  Watson,  Bot.  King's  Expl.  290,  1871. — A.  lenliformis  torreyi. 

RELATIONSHIPS. 

When  taken  in  the  extended  sense  here  adopted,  Alriplex  lenliformis  is  well  set  off 
from  all  other  species.  The  compressed  orbicular  fruiting  bracts  suggest  a  relationship 
with  A.  hymenelytra,  while  the  very  woody  and  subspinose  habit  suggests  connections 
with  A.  conferiifolia.  It  is  more  primitive  than  either  of  these  in  the  retention  of  a 
strong  tendency  toward  monoecism  in  subspecies  breweri  and  lypica. 

The  four  subspecies  are  geographic  as  well  as  morphologic,  as  has  been  mentioned 
in  the  paragraph  introductory  to  the  key,  but  only  subspecies  griffithsi  is  truly  isolated, 
the  ranges  of  the  others  meeting  along  their  borders.  Subspecies  lypica  and  breweri 
are  the  most  difficult  to  distinguish.  The  best  mark  of  the  former  is  the  crenulation  of 
its  fruiting  bracts.  But  plants  with  entire  bracts  are  sometimes  found  well  within  the 
area  of  lypica  and  with  the  other  features  of  this  form  (Bakersfield,  California,  September 
24,  1894,  Easlwood,  Gr,  UC;  Kern  Lake,  Dam/  2911,  UC).  The  crenulations  are  never 
very  pronounced  in  lypica,  which  was  originally  described  by  Torrey  as  "bracteis 
orbicularis  integris  vel  remote  repando  denticulatis,"  and  the  bracts  of  breweri  commonly 
are  at  least  undulate.  The  degree  of  compression  of  the  bracts  also  has  been  used  as 
a  distinguishing  character,  but  without  much  success.  The  impressions  made  upon 
different  botanists  is  indicated  by  the  fact  that,  although  Standley  (N.  Am.  Fl.  21: 
63-64,  1916)  describes  the  bracts  of  breweri  as  strongly  convex  and  those  of  typical 
lenliformis  as  strongly  compressed,  Parish  (Erythea  7:91,  1899)  and  Jepson  (Fl.  Calif. 
440,  1914)  could  see  no  difference  between  breweri  and  orbicularis,  the  bracts  of  the  latter 
also  described  by  Standley  as  strongly  compressed.  Field  studies  indicate  that  the 
bracts  of  breweri  have  a  tendency  to  be  thicker  than  those  of  lypica.  This  is  perhaps 
the  effect  of  the  maritime  habitat  of  the  former.  The  leaves  and  bracts  average  larger 
in  breweri,  as  would  be  expected  in  a  seacoast  form,  and  this  may  in  turn  account  for  the 
smoothing  out  of  the  margins.  Monoecism  is  common  in  breweri,  but  not  wanting  in 
lypica,  for  in  the  San  Joaquin  Valley,  California,  where  this  subspecies  abounds  and 
where  dioecism  is  the  rule,  entire  branches  loaded  with  fruiting  bracts  may  be  found  on 
plants  otherwise  staminate,  while  on  other  plants  the  sexes  are  about  equally  represented, 
the  two  kinds  mixing  in  the  inflorescences.  Specimens  illustrating  these  intergradations 
in  various  characters  are  on  file  in  the  herbarium  of  the  University  of  California. 

Subspecies  typica  is  met  along  the  easterly  part  of  its  range  by  subspecies  lorreyi. 
It  is  not  known  that  they  actually  intermingle,  although  they  have  been  reported  from 
the  same  locality.  The  latter  form  is  more  inclined  to  be  spinescent,  in  keeping  with  its 
more  arid  habitat,  but  its  distinguishing  feature  is  the  development  of  sharp  longitudinal 
ridges  on  the  twigs.  No  exact  intermediates  in  this  respect  are  known,  but  in  a  specimen 
of  lypica  from  Tempe,  Arizona  (September  4,  1901,  Thornber,  UC)  the  branches  of  the 
staminate  inflorescence  are  decidedly  angular,  approaching  in  appearance  those  of 
torreyi.  Subspecies  griffithsi  is  a  httle-known  form  of  southeastern  Arizona,  remarkable 
for  its  narrow  leaves  and  relatively  broad  fruiting  bracts. 


GENUS   ATRIPLEX. 


Atriplex  lentiformis  is  essentially  uniform  in  its  ecological  behavior,  in  spite  of  the 
differences  that  mark  the  subspecies.  It  is  typically  an  intense  halophyte,  as  shown  by 
the  determinations  of  Kearney.  The  salt-content  of  the  first  foot  ranged  from  2.5  to  4 
per  cent,  for  the  second  foot  from  0.72  to  1.38  per  cent,  and  for  the  third  from  0.30  to 
0.57  per  cent.  In  chemical  composition  the  alkali  contained  one-half  NaCl,  one-fifth 
NaHCOj  and  considerable  NajCOj  and  CaS04.  Its  tolerance  of  alkali  is  greater  than  that 
of  any  other  plant  investigated,  and  this  is  in  accord  with  its  dominance  in  the  most 
alkaline  habitats  of  the  Southwest.  The  subspecies  agree  in  constituting  initial  consocies 
that  are  often  pure  and  of  considerable  size.  In  the  case  of  typica  these  may  be  almost 
impenetrable  jungles  acres  in  extent  and  10  to  15  feet  high,  especially  about  the  Salton 
Sea  and  on  the  flood-plain  of  the  Colorado  River.  Breweri  behaves  similarly  in  salt- 
basins  and  on  shores  along  the  coast,  though  regularly  lower  and  less  dense.  Both  forms 
resemble  A.  canescens  in  growing  frequently  on  dunes.  Their  regular  associates  are 
naturally  either  intense  halophytes,  such  as  Suaeda,  Spirostachys,  Sarcobatus,  Salicornia, 
A.  polycarpa,  etc.,  or  species  capable  of  enduring  strong  alkali,  such  as  Distichlis,  Sporo- 
bolus,  Prosopis,  etc. 


The  lenscale,  or  quailbrush,  as  this  saltbush  is  sometimes  called,  is  of  some  value  for 
browse,  especially  by  cattle  in  the  desert  area  and  in  Nevada.  An  analysis  by  Forbes 
and  Skinner  (Ariz.  Agr.  Exp.  Sta.  Rep.  13:269,  1902)  indicates  that  it  contains  less 
protein  and  more  fiber  than  most  species  of  Atriplex.  The  dense  shrubs  provide  a  shelter 
for  rabbits,  quail,  and  other  animals,  a  list  of  which  has  been  prepared  for  the  Lower 
Colorado  Valley  by  Grinnell  (Univ.  Calif.  Publ.  Zool.  12:74,  1914).  The  subspecies 
breweri  is  cultivated  to  a  considerable  extent  on  the  coastal  slope  of  southern  California 
as  an  ornamental  foUage  plant.  Its  greatest  use  is  for  clipped  hedges  in  wind-swept 
places  near  the  ocean. 

The  Coahuilla  Indians  of  southern  California  utilize  the  seeds  of  this  species  for 
food  by  grinding  them  up  and  cooking  with  salt  and  water  (D.  P.  Barrows,  Ethno- 
botany  of  the  Coahuilla  Indians  of  Southern  California  65,  1900).  Notes  on  the 
Indian  uses  of  various  species  of  Atriplex  are  given  by  Standley  (Contr.  U.  S.  Nat. 
Herb.  23:252,  1922). 

44.  ATRIPLEX  CONFERTIFOLIA  (Torrey  and  Fremont)  Watson.  Proc.  Am.  Acad.  9:119. 
1874.  Plate  56.    Shadscale  ;  Spiny  Saltbush. 

Erect  shrub,  very  woody  throughout,  rigidly  branched,  spiny,  of  rounded  outline 
when  normally  developed,  2  to  8  dm.  high;  branches  not  angled,  stout,  erect  or  ascending, 
sparsely  scurfy  at  first,  soon  smooth  and  straw-colored,  the  bark  gray  and  exfoliating  on 
old  basal  stems;  leaves  at  first  crowded,  deciduous  from  the  twigs  which  then  change  into 
spines,  alternate,  short-petioled,  orbicular-ovate,  orbicular-obovate,  or  elliptic,  rounded 
or  cuneate  at  base,  obtuse  at  apex,  1  to  2  cm.  long,  0.5  to  1.2  cm.  wide,  entire,  firm  but 
not  especially  thick,  gray  with  a  close  permanent  scurf,  1-  or  3-nerved  from  the  base; 
flowers  dioecious,  the  staminate  glomerules  in  the  axils  of  reduced  upper  leaves  and  thus 
forming  short  leafy-bracted  spikes,  the  pistillate  solitary  or  several  in  each  of  the  upper 
leaf-axils,  perianth  5-cleft  in  the  staminate  flowers,  wanting  in  the  pistillate;  fruiting 
bracts  sessile,  convex  and  united  over  the  seed,  otherwise  flat  and  free,  nearly  orbicular 
or  broadly  elliptic,  6  to  12  mm.  long,  5  to  10  mm.  broad,  entire  (except  in  minor  variation 
1),  the  faces  smooth;  seed  1.5  to  2  mm.  long,  reddish  brown;  radicle  superior.  {Obione 
confertifolia  Torrey  and  Fremont,  in  Fremont's  Rep.  Rocky  Mts.  Ore.  Calif.  318,  1845.) 


A.    CONFERTIFOLIA.  339 

Dry  alkaline  plains  and  slopes;  Montana,  North  Dakota,  Wyoming,  and  Colorado  to 
Chihuahua  (according  to  Torrey,  Bot.  Mex.  Bound.  183,  1859),  northern  Arizona, 
eastern  CaUfornia  (except  on  the  Colorado  Desert),  eastern  Oregon,  and  southern 
Idaho.  The  most  abundant  species  on  stony  plains  and  hillsides  in  the  Great  Basin. 
Type  locality,  borders  of  Great  Salt  Lake.  Collections:  Colgate,  eastern  Montana, 
Sandberg  894?  (UC) ;  Medora,  North  Dakota,  Lee  606  (NY) ;  Powder  River,  Wyoming, 
Nelson  9Jf20  (Gr) ;  Carter,  Wyoming,  Nelson  4619  (UC) ;  near  Pueblo,  Colorado,  Greene 
(Gr,  UC) ;  Grand  Junction,  Colorado,  May,  1892,  Eastwood  (UC) ;  Naturita,  southwest- 
ern Colorado,  Payson  2S25  (SF,  UC);  Holbrook,  Arizona,  1883,  Rushy  (NY,  UC); 
Navajo  Reservation,  Arizona,  Standley  74-81  (US,  type  of  A.  collina  Wooton  and  Stand- 
ley,  minor  variation  1);  Granite  Wells,  San  Bernardino  County,  California,  Parish  10186 
(DS,  UC);  south  of  Lone  Pine,  Owens  Valley,  California,  Hall  and  Chandler  7315  (UC); 
Honey  Lake  Valley,  California,  Davy  3274  (UC);  Las  Vegas,  Nevada,  Goodding  2314 
(Gr,  NY,  UC);  Palisade,  Nevada,  August  1885,  Brandegee  (UC);  St.  George,  Utah, 
Goodding  795  (DS,  UC);  type  collection,  Utah,  Fremont  (NY);  near  Christmas  Lake, 
eastern  Oregon,  Leiberg  775  (Gr,  NY) ;  Twin  Falls  and  Shoshone  Falls,  Idaho,  Nelson 
and  Macbride  1379  (Gr,  NY,  UC,  type  collection  of  A.  subconferta  Rydberg,  minor 
variation  4);  south  of  Albion,  southern  Idaho,  September  17,  1819,  Hall  (UC).  Addi- 
tional localities  within  the  area  represented  by  the  above  citations  may  be  obtained  in 
abundance  from  herbaria.  Merriam  (N.  Am.  Fauna  7:323,  1893)  gives  details  of  dis- 
tribution in  southern  Nevada  and  California.  Western  McKinley  and  San  Juan  Coun- 
ties, New  Mexico,  are  stations  mentioned  by  Wooton  and  Standley  (Contr.  U.  S.  Nat. 
Herb.  19:205,  1915). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Atriplex  coluna  Wooton  and  Standley,  Contr.  U.  S.  Nat.  Herb.  16:  119,  1913.— Distinguished  from 
typical  confertifolia  by  the  elliptic-obovate  or  rarely  suborbicular  small  leaves  and  especially  by  the  fruiting 
bracts,  which  are  dentate  at  least  near  the  bases  of  the  wings.  Plants  are  sometimes  found  with  the  leaves  of 
the  shape  and  size  characteristic  of  collina,  but  with  bracts  as  in  typical  confertifolia  (Mineral  County,  Nevada, 
Brandegee,  UC;  near  Albion,  Idaho,  Hall,  UC).  The  only  specimens  seen  with  regularly  dentate  bracts 
are  the  types  of  collina.  In  a  specimen  from  Thompson's  Spring,  southeastern  Utah  (Rydberg  and  Garrett  8331, 
NY)  the  leaves  are  as  in  typical  confertifolia,  while  the  bracts  vary  from  entire  through  undulate  to  obtusely 
2-toothed  on  each  margin.  This  indicates  so  much  variation  in  the  characters  used  for  the  separation  of 
collina  that  its  acceptance  as  a  distinct  species  may  be  deferred  at  least  until  better  known.  The  type  locality 
is  the  north  end  of  the  Carrizo  Mountains,  Arizona,  but  the  distribution  is  extended  in  the  North  American 
Flora  to  include  southwestern  Colorado,  southeastern  Utah,  and  northeastern  Arizona. 

2.  A.  CONFERTIFOLIA  X  CANEscENs. — An  Undoubted  hybrid  between  these  species  was  found  at  Winslow, 
.\rizona  {Loft field  and  Hall  11176,  UC).  The  habit  is  that  of  confertifolia;  the  leaves  are  intermediate,  being 
elliptic-oblong  and  elliptic-spatulate,  1  to  2  cm.  long,  0.4  to  1  cm.  wide;  the  fruiting  bracts  vary  all  the  way 
from  those  of  confertifolia  to  equally  4-winged,  as  in  canescens,  many  of  them  with  a  pair  of  flat  terminal  wings 
and  one  or  two  divergent  basal  lobes.  Some  of  the  seeds  are  shriveled  and  infertile,  others  appear  to  be  normal, 
and  these  probably  are  viable.  Both  of  the  supposed  parents  grew  on  the  hillside  where  the  specimen  was 
collected. 

3.  A.  SPINOSA  Dietrich,  Syn.  PI.  5:  536,  1852. — Based  upon  Obione  spinosa,  which  see. 

4.  A.  SUBCONFERTA  Rydberg,  Fl.  Rocky  Mts.  248,  1917.— Separated  from  A.  confertifolia  on  the  basis  of 
its  oblanceolate,  acute  or  acutish  leaves  and  its  lance-oblong  usually  acute  bracts.  The  type  specimen,  which 
came  from  "Twin  Falls  and  Shoshone  Falls,"  Idaho  (Nelson  and  Macbride  1379)  appears  to  be  abnormally 
developed.  In  one  of  the  duplicates  of  the  type  at  the  University  of  California  some  of  the  bracts  have  a  very 
small  body  and  narrow,  lanceolate  wings,  while  other  bracts  on  the  same  stem  have  well-formed  bodies  and 
ovate,  obtuse  wings.  Bracts  of  the  latter  type  are  8  mm.  long  by  6  mm.  broad.  The  foliage  is  not  exactly 
like  that  of  any  specimen  seen  of  genuine  confertifolia,  the  leaves  being  exceptionally  narrow  in  proportion  to 
their  length. 

5.  Obione  confertifolia  Torrey  and  Fremont,  in  Fremont,  Rep.  Calif.  318,  1845.— The  original  name  of 
Atriplex  confertifolia. 

6.  O.  SPINOSA  Moquin,  in  DeCandolle,  Prodr.  13':  108,  1849.— Universally  regarded  as  a  synonym  of  the 
earlier  0.  confertifolia,  which,  from  the  description,  it  appears  to  be.  Based  upon  plants  gathered  somewhere 
on  the  drainage  basin  of  the  Columbia  River  by  Nuttall. 


340  GENUS   ATRIPLEX. 

RELATIONSHIPS. 

Alriplex  confertifolia  is  the  central  and  by  far  the  most  abundant  and  widespread 
member  of  a  close  group  of  three  species,  the  other  two  being  spinifera  and  parryi.  All 
of  these  have  developed  a  decidedly  spinose  habit,  which,  however,  is  found  also  in 
certain  forms  of  A.  leniiformis,  a  species  otherwise  very  different.  In  addition  to  the 
spinose  habit,  the  confertifolia  group  is  marked  by  characters  of  the  fruiting  bracts  not 
found  elsewhere  in  the  genus.  The  bracts  of  each  pair  are  firmly  united  at  the  base 
into  a  small  indurated  thickened  body  from  the  upper  portion  of  which  the  free  margins 
are  developed  into  a  pair  of  thin,  flat  wings  standing  face  to  face  and  much  broader 
than  the  body  itself.  Differences  in  the  shape  of  the  body  and  in  the  size  and  shape 
of  the  wings  constitute  the  principal  characters  used  to  differentiate  the  species  of  the 
group. 

ECOLOGY. 

Atriplex  confertifolia  ranks  next  to  Artemisia  tridentata  in  importance  as  a  consocia- 
tion of  the  Basin  sagebrush  association.  In  Nevada  it  is  often  more  abundant  than 
sagebrush,  owing  to  the  prevalence  of  hard,  stony,  alkaline  soils  on  benches  and  slopes. 
Over  much  of  its  range  it  regularly  mixes  or  alternates  with  Artemisia  and  its  associates, 
such  as  Grayia,  Chrysothamnus,  and  Tetradymia.  It  endures  alkaline  soils  better  than 
most  of  these  and  its  most  typical  position,  both  as  to  topography  and  succession,  is 
in  a  zone  between  such  strongly  halophytic  dominants  as  Sarcobatus  or  Atriplex  nut- 
talli  and  corrugata  on  the  one  hand  and  sagebrush  on  the  other.  It  may  even  occur 
on  alkali  flats  with  such  marked  halophytes  as  Salicornia,  and  is  frequently  associated 
with  Kochia  vestita,  and  in  Nevada  with  Artemisia  spinescens.  It  is  a  characteristic  domi- 
nant of  the  bad  lands  of  the  Great  Basin,  especially  the  Cretaceous  ones  of  the  Mancos, 
Fort  Steele,  and  Lewis  formations,  covering  the  less  alkaline  slopes  between  Atriplex 
nuttalli  at  the  base  and  the  sagebrush  climax  above. 

Kearney,  Briggs,  Shantz,  McLane,  and  Piemeisel  have  found  the  salt-content  to 
range  from  0.06  per  cent  in  the  first  foot  to  0.09  per  cent  in  the  fourth  foot  where  the 
plants  were  exceptionally  large  and  healthy,  while  the  average  range  was  from  0.07  in 
the  first  foot  to  0.93  per  cent  in  the  fourth  foot  (Indicator  significance  of  vegetation  in 
Tooele  Valley,  Utah.     Jour.  Agr.  Res.  1:396,  1914). 

USES. 

Chiefly  because  of  its  great  abundance  over  large  areas  where  other  browse  and 
forage  plants  are  scarce,  the  shadscale  is  of  much  value  to  the  stock  interests  in  western 
North  America.  It  is  used  especially  as  a  winter  browse  for  sheep  in  Nevada  and 
adjacent  States  and  to  some- extent  also  for  cattle,  the  spines,  however,  interfering  with 
its  use  by  the  latter.  Otherwise  the  species  is  of  economic  interest  only  as  a  cause  of 
hay-fever.  It  is  almost  certain  that  the  pollen  extracts  could  be  advantageously  used 
for  purposes  of  desensitization  against  this  malady  in  the  case  of  some  patients,  as 
explained  under  A.  rosea  (p.  260). 

45.  ATRIPLEX  SPINIFERA  Macbride,  Contr.  Gray  Herb.  n.  s.  53:11,  1918.      Plate  57. 
Spinescale. 

Erect  shrub,  very  woody  throughout,  rigidly  branched  and  spiny,  normally  much 
taller  than  broad,  3  to  15  dm.  high;  branches  not  angled,  but  sometimes  striate,  stout, 
mostly  erect,  white-scurfy  at  first,  glabrate  but  still  very  pale,  the  old  bark  gray,  splitting 
longitudinally  on  the  surface  and  exfoliating;  leaves  either  crowded  or  rather  sparse, 
deciduous  from  the  twigs  which  then  become  modified  into  rigid  horizontal  or  widely 
divergent  spines,  alternate,  mostly  short-petioled,  the  upper  sessile,  deltoid-ovate  or 
elliptic,  cuneate  at  the  base  or  the  sessile  ones  truncate,  obtuse  at  apex,  1  to  2  cm. 
long,  0.5  to  1.5  cm.  wide  (undeveloped  leaves  of  the  ultimate  twigs  often  much  smaller, 
as  in  the  type  specimen),  entire  or  especially  those  on  sterile  shoots  subhastate,  thinnish, 


A.    SPINIFERA A.    PARRYI.  341 

gray  or  nearly  white  with  a  close  permanent  scurf,  1-nerved  from  the  base;  flowers 
dioecious,  the  staminate  not  known,  the  pistillate  soUtary  or  in  small  glomerules  in  the 
upper  leaf-axils;  perianth  wanting  in  the  pistillate  flowers;  fruiting  bracts  closely  sessile 
and  adjacent  pairs  often  fused  at  base,  the  body  globoid  or  slightly  longer  than  broad 
(4  to  6  mm.  thick),  the  free  margins  developed  above  the  body  into  orbicular  or  oblong 
wings,  the  whole  bract  7  to  15  mm.  long,  3.5  to  10  mm.  broad,  entire  or  the  wings  irregu- 
larly dentate,  the  faces  either  smooth  or  with  a  few  cristate  appendages;  seed  2  to  2.8 
mm.  long,  reddish-brown;  radicle  superior. 

California,  from  the  westerly  side  of  the  San  Joaquin  Valley  to  the  western  part  of  the 
Mojave  Desert.  Type  locality,  Maricopa  Hills,  Kern  County,  California.  Collections, 
all  in  California:  1.5  km.  north  of  Volta,  Merced  County,  Severin  and  Hall  11018  (UC); 
western  Fresno  County,  5  km.  south  of  South  Dos  Palos,  Severin  and  Hall  11021,  11754 
(UC);  Mendota,  western  Fresno  County,  Severin  and  Hall  11761  (UC);  5  km.  south  of 
Shafter,  Kern  County,  Severin  and  Hall  11779  (UC);  type  collection.  May  15,  1913, 
Eastwood  S269  (Or);  Buena  Vista  Hills,  Kern  County,  April  9,  1893,  Eastwood  (UC, 
pocket) ;  base  of  Fremonts  Peak,  Inyo  County,  Hall  and  Chandler  6866  (UC) ;  Dry  Lake, 
near  Rosamond,  Antelope  Valley,  Hall  10581  (UC);  Kramer,  Mojave  Desert,  Brandegee 
(UC);  Daggett,  Mojave  Desert,  Brandegee  (UC). 

RELATIONSHIPS. 

Atriplex  spinifera  is  a  far-western  development  from  A.  confertifolia,  which  it  resembles 
in  the  spiny  habit  and  in  the  general  features  of  the  inflorescence  and  fruiting  bracts. 
The  branches  are  more  nearly  erect  than  in  confertifolia  and  the  plants  therefore  less 
rounded  and  spreading.  The  hastate  tendency  evident  in  the  summer  foliage  is  not 
known  in  the  other  species  and  the  thick-bodied  bracts,  contracted  just  beneath  the  wing- 
like free  terminal  margins,  are  distinctive.  During  the  late  summer  the  broader  subhas- 
tate  leaves  drop  off,  leaving  only  the  small  entire  ones  of  the  twigs,  but  the  fruiting 
bracts  persist  into  the  late  autumn.  The  type  specimens  consist  only  of  twigs  and 
bracts  gathered  in  May,  and  do  not  show  the  larger,  hastate  leaves  which  may  not  have 
been  present  on  the  plants  at  that  period.  The  bracts,  too,  are  undersized  and  look  as 
though  they  came  from  a  plant  flowering  out  of  season.  This  accounts  for  certain  dis- 
crepancies between  the  original  description  and  the  one  given  above. 
ECOLOGY  AND  USES. 

Atriplex  spinifera  attains  its  best  development,  both  in  size  and  abundance,  on  the 
moderately  alkaline  plains  of  western  San  Joaquin  Valley  in  California.  It  forms  open 
stands,  often  pure,  but  sometimes  mixed  with  A.  polycarpa,  or  in  Antelope  Valley  with 
the  closely  related  confertifolia.  It  may  also  grow  on  low  alkaline  mounds,  with  the  inter- 
vening flats  occupied  by  Gastridium,  Trichostema,  Eremocarpus,  Frankenia,  and  Salsola. 
It  is  a  marked  halophyte,  apparently  intermediate  between  polycarpa  and  confertifolia 
in  its  tolerance  of  alkali. 

There  is  no  evidence  that  this  species  has  any  economic  value,  though  it  may  be  occa- 
sionally browsed  by  sheep.  The  beet  leaf-hopper  {Eutettix  tenella)  has  been  bred  from 
it,  and  Severin  believes  that  it  is  an  important  winter  food-plant  of  this  insect.  (See 
further  under  A.  bracteosa,  p.  307.) 

46.  ATRIPLEX  PARRYI  Watson,  Proc.  Am.  Acad.  17:378,  1882.  Plate  57. 
Erect  shrub,  woody  throughout,  rigidly  branched,  spiny,  of  rounded  outline,  2  to  4 
dm.  high;  branches  not  angled,  slender,  erect  or  ascending,  white-scurfy,  glabrate  and 
then  straw-colored,  the  old  bark  becoming  dark  and  longitudinally  broken ;  leaves  at  first 
crowded,  deciduous  from  the  twigs  whfch  are  then  transformed  into  spines,  alternate, 
sessile,  orbicular-ovate  or  subreniform,  cordate  or  subcordate  at  base,  obtuse  at  apex 
or  those  of  the  inflorescence  acute,  0.5  to  1.2  cm.  long,  0.7  to  1.5  cm.  wide,  entire,  thin. 


342  GENUS   ATRIPLEX. 

gray  or  whitish  with  a  close  permanent  scurf.  1-  or  3-nerved  from  the  base;  flowers  dioe- 
cious, the  staminate  glomerules  in  the  upper  axils,  forming  dense  leafy-bracted  panicles, 
the  pistillate  1  to  several  in  each  of  the  upper  axils,  thus  forming  small  panicles;  perianth  of 
staminate  flowers  5-cleft  (as  far  as  known),  wanting  in  the  pistillate;  fruiting  bracts  sessile 
or  very  shortly  stalked,  compressed  but  thick  and  rigid,  united  to  above  the  middle  and 
sometimes  to  the  broad  summit,  forming  a  compressed-campanulate  sac  bordered  above 
by  the  thick  margins,  truncate-flabelliform  when  pressed,  3  to  4  mm.  long,  3.5  to  4.5  mm. 
broad,  entire,  the  face  smooth;  seed  1  to  1.5  mm.  long,  brown  or  amber;  radicle  superior. 
From  the  Mojave  Desert,  California,  to  western  Nevada.  Type  locality,  Lancaster, 
Mojave  Desert,  California  (according  to  Parish,  Zoe  5:113,  1901).  Collections,  all  in 
Cahfornia  except  the  last:  Type  collection,  1881,  Parry  282  (Gr);  near  Lancaster,  Bran- 
degee  (UC);  near  Rosamond  and  Dry  Lake,  Antelope  Valley,  Davy  2190,  2195,  2227, 
2232,2946,  294?  (UC);  near  Troy,  Mojave  Desert,  Johnston  4092  (Pomona);  Rab- 
bit Springs,  Mojave  Desert,  Parish  1350  in  part  (US);  near  Keeler,  Inyo  County, 
Coville  and  Funston  843  (DS,  Gr,  NY,  US);  Resting  Springs  Valley,  Inyo  County, 
CoviUe  and  Funston  274  (US);  Beattie,  Nevada,  Heller  10421  (DS,  Gr,  NY,  US). 
Additional  locahties  recorded  by  Coville  (Contr.  U.  S.  Nat.  Herb.  4:181,  1893)  are 
the  following:  Cahfornia:  Rabbit  Springs,  Mojave  Desert,  Death  Valley,  west  shore 
of  Owens  Lake,  north  of  Searles,  between  Lone  Pine  .and  Big  Pine;  Nevada:  Ash 
Meadows,  Oasis  Valley,  Grapevine  Canon,  Sarcobatus  Flat. 

RELATIONSHIPS. 

This  species  is  of  the  confertifolia  group,  but  does  not  closely  approach  the  others.  It  is 
much  more  slender-twigged  than  either  confertifolia  or  spinifera  and  is  readily  distin- 
guished from  either  of  these  by  the  closely  sessile  subcordate  leaves.  The  fruiting  bracts 
differ  from  those  of  related  species  in  the  absence  of  free,  thin,  terminal,  wing-like  margins, 
the  summit  consisting  instead  of  a  truncate  thick  border  around  the  orifice  formed  by  the 
united  bracts.  Although  probably  derived  from  A.  confertifolia,  it  is  not  isolated  from 
this,  for  the  two  grow  near  each  other  at  many  places  within  the  limited  area  of  A.  parryi. 
ECOLOGY  AND  USES. 

Atriplex  parryi  is  an  intense  halophyte  of  the  desert  area  of  eastern  California  and 
southern  Nevada,  apparently  with  a  tolerance  close  to  that  of  lentiformis  and  polycarpa. 
It  is  abundant  or  even  dominant  in  alkaline  flats,  and  also  invades  the  edge  of  the  desert 
scrub  about  the  margin,  where  it  mingles  with  Larrea.     It  is  not  known  to  be  of  use. 

47.  ATRIPLEX  CANESCENS  (Pursh)  Nuttall,  Gen.  PI.  1:197,  1818.    Plate  58. 

WiNGSCALE.' 

Erect  shrub,  woody  throughout,  loosely  to  densely  branched  and  exceedingly  variable 
in  outline,  2  to  25  dm.  high;  branches  terete,  stout,  gray-scurfy,  glabrate  and  then  pale, 
the  old  bark  gray  and  splitting  on  the  surface,  after  which  it  exfoliates;  leaves  numerous, 
alternate,  sessile  or  subsessile,  linear  to  spatulate-oblong  or  broadly  elliptic,  narrowed 
at  the  base,  usually  obtuse  at  apex  (except  in  subspecies  garretti),  1  to  5  cm.  long,  0.1  to 
1  cm.  wide  (up  to  1.8  cm.  wide  in  garretti), enine,  thick,  gray  with  a  dense  permanent  scurf, 
1-nerved;  flowers  dioecious  (or  rarely  monoecious,  according  to  Standley),  the  staminate 
glomerules  in  dense  spikes  of  long  terminal  panicles,  these  leafy  below,  the  pistillate  in 
dense  leafy-bracted  spikes  and  panicles;  perianth  4-  or  5-cleft  in  staminate  flowers, 
wanting  in  the  pistillate;  fruiting  bracts  sessile  or  stalked,  the  body  not  compressed,  firmly 
united  to  the  summit  of  the  body,  above  which  the  free  tips  project  as  flat  wings,  the  whole 
bract  4  to  12  or  rarely  20  mm.  long,  above  as  broad,  the  margins  developed  into  a  pair  of 
flat,  broad  wings,  a  second  pair  of  wings  developed  also  from  the  medial  line  of  each 

'  Atriplex  canetcens  is  sometimes  called  "shadacale,"  a  wholly  inappropriate  name  for  this  species.  The  term  shadscale 
is  here  restricted  to  A.  confertifolia,  to  which  also  it  has  been  applied  in  the  literature  and  the  fruiting  bracts  of  which  it 
aptly  describes. 


A.    CANESCENS.  343 

exposed  face,  the  four  wings  thus  formed  entire  to  laciniate,  the  faces  smooth  or  with 
small  appendages  between  the  wings;  seed  1.5  to  2.5  mm.  long,  brown;  radicle  superior. 
{Calligonum  canescens  Pursh  Fl.  Am.  Sept.  370,  1814.) 

Widely  distributed  in  western  North  America;  Alberta  to  Kansas,  western  Texas, 
Zacatecas,  Lower  California,  eastern  Washington,  and  Montana. 

SUBSPECIES. 

Key  to  the  Subspecies  of  Atriplex  canescens. 
Leaves  linear  to  oblong  or  wider,  2  mm.  or  more  wide;  fruiting  bracts  6  to  15  mm.  or  more 
long,  or  if  shorter  the  leaves  then  4  mm.  or  more  wide. 
Blade  of  leaf  usually  widest  above  middle,  linear-spatukte  to  oblong-spatulate,  0.2  to 
1.2  cm.  wide. 

Shrub  normally  4  to  15  dm.  high;  leaves  linear-spatulate  or  narrowly  oblong (a)  typica  (p.  343). 

Shrub  2  to  4  dm.  high;  leaves  oblong  or  oblong-spatulate (b)  aplera  (p.  343). 

Blade  of  leaf  widest  at  middle,  broadly  elliptic,  0.8  to  1.8  cm.  wide.     Shrub  under 

4  dm.  high (c)   garretli  (p.  344). 

Leaves  linear,  mostly  2  mm.  or  less  wide;  fruiting  bracts  4  to  8  or  rarely  10  mm.  long. 

Fruiting  bracts  sessile  or  nearly  so,  the  stalks  2  mm.  or  less  long (d)  linearis  (p.  344). 

Fruiting  bracts  on  stalks  4  to  10  mm.  long (e)  macropoda  (p.  344) . 

47a.  Atriplex  canescens  typica. — Shrub  4  to  15  dm.  high;  leaves  linear-spatulate 
or  narrowly  oblong,  mostly  widest  above  the  middle,  obtuse  or  barely  acute  at  apex,  1.5 
to  4  or  rarely  5  cm.  long,  0.2  to  0.8  cm.  wide;  fruiting  bracts  (including  wings)  6  to  15  or 
rarely  20  mm.  long,  on  straight  or  recurved  stalks  2  to  15  mm.  long;  wings  4  to  8  or 
rarely  12  mm.  wide  (reduced  to  2  to  4  mm.  wide  in  variety  macilenta  Jepson,  minor  vari- 
ation 6;  broad,  thin,  and  deeply  laciniate  in  variety  laciniata  Parish,  minor  variation  5), 
usually  much  exceeding  the  triangular  free  terminal  portion  of  the  bracts.  {Calligonum 
canescens  Pursh,  Fl.  Am.  Sept.  370,  1814.)  South  Dakota  to  Kansas,  western  Texas, 
Zacatecas,  Lower  California,  eastern  Washington,  and  Idaho;  by  far  the  most  common 
form  almost  throughout  western  North  America.  Type  locality,  plains  of  the  Missouri 
River,  near  the  Big  Bend,  South  Dakota.  Collections:  Natrona  County,  Wyoming, 
Goodding  246  (NY) ;  Uva,  Laramie  County,  Wyoming,  Nelson  8584  (UC) ;  near  Denver, 
Colorado,  Eastwood  112  (UC);  Grove  County,  Kansas,  Hitchcock  44O  (Or,  NY);  Redford, 
western  Texas,  Hanson  812  (Gr);  Animas  Creek,  Sierra  County,  New  Mexico,  Metcalfe 
1124  (Gr,  SF,  NY);  6  km.  northwest  of  Tucson,  Arizona,  Thornber  111  (NY,  UC);  Casas 
Grandes,  Chihuahua,  Goldman  423  (Gr);  near  Saltillo,  Coahuila,  Palmer  298  (Gr,  UC, 
US) ;  San  Luis  Potosi,  Schaffner  35  (Gr) ;  Cedros,  Zacatecas,  Lloyd  36  (US) ;  San  Gregorio, 
Lower  California,  February  6,  1889,  Brandegee  (UC);  South  Coronado  Island,  Lower 
California,  Parish  8836,  8837  (UC);  Caleb,  Colorado  Desert,  California,  Parish  8256 
(Gr,  tj^e  collection  of  A.  canescens  laciniata  Parish,  minor  variation  5);  Salton  Creek, 
Colorado  Desert,  California,  April  3,  1901,  Brandegee  (UC);  Glendale  to  Burbank,  Los 
Angeles  County,  California,  Braunion  906  (UC) ;  Clark  County,  Nevada,  Heller  10980 
(UC);  Reno,  Nevada,  June,  1890,  Sonne  (UC);  Alvord  Desert,  eastern  Oregon,  Cusick 
2595  (UC);  near  Spokane,  Washington  (R);  Pocatello,  Idaho,  Nelson  and  Macbride  1397 
(UC).  Numerous  additional  localities  may  be  secured  by  consulting  herbaria.  Detailed 
distribution  in  eastern  California  and  southern  Nevada  is  given  by  Merriam  (N.  Am. 
Fauna   7:326,    1893). 

476.  Atriplex  canescens  aptera  (Nelson). — Shrub  2  to  4  dm.  high;  leaves  oblong 
to  oblong-spatulate,  mostly  widest  above  the  middle,  obtuse  at  apex,  2  to  4  cm.  long, 
0.4  to  1.2  cm.  wide;  fruiting  bracts  4  to  8  mm.  long,  on  stout  erect  or  spreading  stalks  1 
to  5  mm.  long  or  some  sessile;  wings  1  to  5  mm.  wide,  sometimes  1  or  more  of  them  wanting 
(in  the  type  material),  about  equaling  or  slightly  exceeding  the  free  terminal  portion  of 
the  bracts.  {A.  aptera  Nelson,  Bot.  Gaz.  34:356,  1902.)  Southern  Alberta  to  northern 
Colorado.  Type  locality,  Laramie,  Wyoming.  Collections:  Rosedale  Trail,  Alberta, 
Moodie  986  (DS,  Gr,  NY,  SF,  US) ;  Deer  Lodge,  Montana,  October,  1888,  Anderson  (US); 
type  collection,  September,  1901,  E.  Nelson  738  (Wyo.);  type  locality,  on  saline  flats,  A. 


344  GENUS   ATRIPLEX. 

Nelson  8653  (Gr,  NY,  US)  and  8675  (UC) ;  type  locality,  along  border  of  an  alkaline  draw 
just  west  of  Laramie,  Johnston  2331  (UC). 

47c.  Atriplex  canescens  garretti  (Rydberg). — Shrub  about  3  dm.  high;  leaves 
broadly  elliptic,  widest  across  the  middle,  acute  or  slightly  rounded  at  apex,  1  to  3.5  cm. 
long,  0.8  to  1.8  cm.  wide;  fruiting  bracts  6  to  12  mm.  long,  sessile  or  subsessile;  wings  2  to 
3  mm.  wide,  usually  but  not  always  exceeded  by  the  free  terminal  portion  of  the  bracts. 
{A.  garretti  Rydberg,  Bull.  Torr.  Club  39:312,  1912.)  Eastern  Utah  and  western  Colo- 
rado. Tjrpe  locality,  vicinity  of  Moab,  Utah.  Collections:  Type  collection,  1,200  to 
1,500  m.  altitude,  Rydberg  and  Garrett  8465  (NY);  above  Palisade,  Colorado,  Crandall 
112    (Gr). 

Aid.  Atriplex  canescens  linearis  (Watson). — Shrub  4  to  20  or  25  dm.  high;  leaves 
nearly  linear,  tending  to  widest  above  the  middle,  acute  or  obtuse  at  apex,  1  to  3  or  rarely 
5  cm.  long,  0.1  to  0.25  cm.  wide;  fruiting  bracts  4  to  8  mm.  long,  on  short  stalks  less  than 
2  mm.  long,  or  sessile;  wings  1  to  4  mm.  wide,  usually  exceeded  by  the  lanceolate  free 
terminal  portion  of  the  bracts  but  this  feature  variable.  {A.  linearis  Watson,  Proc.  Am. 
Acad.  24:72,  1889.)  Arizona  to  Sonora,  Lower  California,  and  the  Colorado  Desert  of 
Alta  California.  Type  locality,  alkaline  soil  about  Guaymas,  Sonora.  Collections: 
Phoenix,  Arizona,  Griffiths  5895,  6179,  6181  (US);  Tempe,  Arizona,  Kearney  118,  133 
(US);  Maricopa,  Arizona,  September  3,  1901,  Thornber  (NY,  US);  6  km.  northwest  of 
Tucson,  Arizona,  Thornber  110  (DS,  UC);  Guaymas,  Sonora,  Palmer  120,  121,  235  (Gr, 
NY,  US,  all  cited  with  the  original  description,  only  235  in  mature  fruit  at  the  Gray 
Herbarium);  Las  Animas  Bay,  Lower  California,  Johnston  3490  (SF,  UC);  La  Paz, 
Lower  California,  Johnston  3041  (SF,  UC) ;  Agua  de  San  Esteban,  north  of  San  Ignacio, 
Lower  California,  Nelson  and  Goldman  7207  (US);  Durmid,  Salton  Sea,  California, 
Parish  8073  (DS,  Gr).     See  further  under  minor  variations  1  and  17. 

47e.  Atriplex  canescens  macropoda  (Rose  and  Standley). — Shrub,  the  size  not 
known;  leaves  nearly  linear,  tending  to  widest  above  the  middle,  obtuse  at  apex,  1  to  2 
cm.  long,  0.1  to  0.15  cm.  wide;  fruiting  bracts  (including  wings)  6  to  10  mm.  long,  on  slen- 
der stalks  4  to  10  mm.  long;  wings  2  to  4  mm.  wide,  much  exceeded  by  the  oblong  to  tri- 
angular free  portion  of  the  bracts.  (A.  macropoda  Rose  and  Standley,  N.  Am.  Fl.  21: 
72,  1916.)  Known  only  from  the  type  collection,  Pinchilinque  Island,  Gulf  of  California, 
Rose  16618  {'!<iY,VS). 

MINOR  VARIATIONS  AND  SYNONYMS. 

1.  Atriplex  angustior  Cockerell,  Proc.  Davenport  Acad.  9:  7,  1902. — Based  upon  Obione  occidentalis 
angustifolia,  which  see  in  this  list.  In  New  Mexico  the  angustior  form  produces  flowers  and  fruits  a  month 
or  six  weeks  earher  than  typica,  according  to  Wooton  and  Standley  (Contr.  U.  S.  Nat.  Herb.  19:  204,  1915). 

2.  A.  APTERA  Nelson,  Bot.  Gaz.  34:  356,  1902. — A.  canescens  aptera. 

3.  A.?  BERLANDiERi  Moquin,  Chenop.  Enum.  65,  1840. — From  the  description  this  appears  to  be  'A. 
canescens  typica  with  undeveloped  fruiting  bracts.  It  is  reduced  to  this  species  by  most  writers  on  the  genus. 
The  type  came  from  Mexico. 

4.  A.  CANESCENS  var.  angustifolia  Watson,  Proc.  Am.  Acad.  9:  121, 187i.— Based  upon  Obione  occidentalis 
angustifolia,  which  see. 

5.  A.  CANESCENS  var.  laciniata  Parish  in  Jepson,  Fl.  Calif.  442,  1914. — A  form  of  A.  canescens  typica  in 
which  the  wings  of  the  fruiting  bracts  are  6  to  8  mm.  broad,  thin,  and  saliently  laciniate.  Variation  in  the 
wings  from  entire  through  deeply  toothed  to  cut  into  narrow  lobes  has  been  noted  by  Torrey  (Bot.  Mex.  Bound. 
184,  1859,  under  Obione  occidentalis).  A  form  with  similarly  laciniate,  but  narrow  and  thick  wings,  has  been 
described  as  A.  odontoptera  Rydberg  (No.  11  of  this  list).  Such  variations  are  too  numerous  to  render  feasible 
their  taxonomic  recognition  when  the  species  as  a  whole  is  taken  into  account.  Type  locality,  Caleb,  Colorado 
Desert,  California.  Collections:  type  collection,  Parish  8256  (Gr);  Dos  Palmas,  in  the  same  district,  January 
21,  1921,  Childs  (UC);  near  Newberry,  Mojave  Desert,  1907,  Morefort  (Pomona). 

6.  A.  CANESCENS  var.  macilenta  Jepson,  Fl.  Calif.  442,  1914.— As  to  fruiting  bracts,  this  is  the  opposite 
extreme  from  variety  laciniata,  the  wings  being  much  reduced,  1.5  to  3  mm.  broad,  and  only  dentate.  Accord- 
ing to  Jepson,  macilenta  is  not  uncommon  in  the  southern  part  of  the  Colorado  Desert  and  has  an  aspect  very 
different  from  typical  canescens.    Type  locality,  Holtville,  California.    Not  seen. 


A.    CANESCENS.  345 

7.  A.  GARRETTi  Rydberg,  Bull.  Torr.  Club  39:  312,  1912.— A.  ca7iescens  garretti. 

8.  A.  Li>fEARis  Watson,  Proc.  Am.  Acad.  24:  72,  1889. — A.  canescens  linearis. 

9.  A.  MACROPODA  Rose  and  Standley,  N.  Am.  Fl.  21:  72,  1916. — ^.4.  canescens  macropoda. 

10.  A.  occiDENTALis  Dietrich,  Syn.  PI.  5:  537,  1852. — The  same  as  Pterochilon  occidenlale,  which  see. 

11.  A.  ODONTOPTERA  Rydbcrg,  Bull.  Torr.  Club  31:404,  1904. — A  form  in  which  the  thick  wings  of  the 
fruiting  bracts  are  irregularly  laciniate-dentate.  Perhaps  best  referred  to  A.  aptera  (A.  canescens  aptera  of 
this  treatment),  as  proposed  by  Rydberg  (Fl.  Rocky  Mts.  249,  1917).  Variation  in  the  wings  is  noted  under 
No.  5  of  this  list. 

12.  A.  TETRAPTERA  Rydberg,  Bull.  Torr.  Club  39:  311,  1912.^Based  upon  Obione  tetraptera,  which  see. 

13.  Calligonum  canescens  Pursh,  Fl.  Am.  Sept.  370, 1814. — The  original  description  of  A.  canescens  typica. 

14.  Obione  berlandieri  Moquin,  in  DeCandoUe,  Prodr.  13-:  114,  1849. — Based  upon  Atriplex  berlandieri, 
which  see. 

15.  0.  canescens  Moquin,  Chenop.  Enum.  74,  1840. — The  same  as  Calligonum  canescens. 

16.  0.  OCCIDENTALIS  MoQuin,  in  DeCandoUe,  Prodr.  13':  112,  1849. — Based  upon  Pterochilon  occidenlale, 
which  see. 

17.  0.  OCCIDENTALIS  var.  ANGUSTIFOLIA  Torrey,  Bot.  Max.  Bound.  184,  1859. — Leaves  narrowly  linear 
or  lanceolate-linear,  otherwise  as  in  A.  canescens  typica.  Perhaps  referable  to  subspecies  linearis.  The  types 
came  from  the  Valley  of  the  Rio  Grande. 

18.  O.  tetraptera  Benthain,  Bot.  Voy.  Sulph.  48,  1844. — A  form  of  A.  canescens,  differing  from  the  type 
form  "in  its  narrow,  linear  leaves,  only  2  to  5  mm.  wide,  in  its  more  strongly  reticulate  fruit  wings,  which 
have  a  broad  sinus  at  the  apex,  and  in  that  the  free  portion  of  the  bracts  is  less  than  half  as  long  as  the  width 
of  the  wing"  (Rydberg,  Bull.  Torr.  Club.  39:  311,  1912).  It  is  now  known  that  no  one  of  these  characters 
is  sufficiently  constant,  nor  do  any  two  of  them  vary  in  unison  to  such  an  extent  as  to  render  of  any  value 
the  recognition  of  tetraptera  as  a  species  or  as  a  subspecies.  The  type  came  from  the  coast  of  California  and 
probably  from  San  Diego,  where  plants  answering  the  description  can  now  be  found  (e.  g..  Hall  11216,  UC), 
but  plants  with  the  same  combination  of  characters  grow  as  far  inland  as  Utah  (of.  Rydberg,  Rocky  Mt.  Fl., 
249,  1917).     Bentham  made  no  reference  to  the  earlier  Calligonum  canescens  in  connection  with  his  description. 

19.  Pterochiton  CANESCENS  Nuttall,  Jour.  Acad.  Phila.  II,  1:  184,  1847. — The  same  as  A.  canescens. 

20.  P.  occiDENTALE  Torrey  and  Fremont,  in  Fremont,  Rep.  Rocky  Mts.  Ore.  Calif.  318,  1845.^The  form 
of  A.  canescens  typica  in  which  the  leaves  are  linear-oblanceolate  and  the  strongly  veined  wings  of  the  fruit- 
ing bracts  4  to  6  mm.  or  more  wide,  the  margins  only  sinuate  or  dentate.  Described  without  reference  to 
Calligonum  canescens,  the  original  name  for  the  species,  which  apparently  was  overlooked. 

RELATIONSHIPS. 

Although  one  of  the  most  widely  distributed  of  American  Atriplexes,  this  species  exhib- 
its almost  no  tendency  to  intergrade  with  any  other.  Its  most  distinctive  feature  is  the 
development  of  dorsal  as  well  as  lateral  wings  from  the  fruiting  bracts  so  that  the  whole 
body  comes  to  be  4-winged.  In  subspecies  aptera  there  is  sometimes  a  decided  reduction 
in  these  wings,  and  they  are  even  wanting  in  a  few  bracts  of  this  form.  Since  aptera  has 
also  the  merely  subshrubby  habit  and  the  broad  leaves  of  A.  nuttalli,  it  may  be  that  it 
represents  an  intermediate  stage  in  the  evolution  of  canescens,  but  it  is  also  possible  that 
it  is  a  hybrid,  notwithstanding  its  apparently  fertile  seeds.  The  infrequent  occurrence 
and  the  widely  separated  localities  where  it  has  been  gathered,  all  within  the  general  range 
of  the  supposed  parents,  suggest  a  hybrid  origin.  A  series  of  bracts  from  the  type  of 
aptera  are  shown  in  plate  58.  Some  of  these  are  not  very  unlike  bracts  frequently 
found  in  A.  nuttalli  (cf.  plate  51  and  fig.  46,  p.  326).  Whatever  the  origin  of  subspecies 
aptera  may  be,  the  evidence  as  far  as  available  points  toward  A.  nuttalli  as  the  nearest 
relative  of  A.  canescens. 

The  five  subspecies  here  accepted  fall  into  two  natural  groups.  One  of  these  includes 
typica,  which  is  by  far  the  most  common  and  widely  distributed  of  all,  aptera,  already 
discussed,  and  garretti.  This  last  is  too  little  known  to  permit  of  definite  placing  in  the 
phylogenetic  scheme.  Its  exceptionally  broad  and  veiny  leaves  are  unlike  anything 
known  in  genuine  canescens,  although  the  bracts  are  exactly  as  in  the  common  typical 
form.  The  leaf  characters  suggest  a  connection  with  A.  obovata,  but  there  is  no  evidence 
that  these  two  intergrade  or  hybridize.  Further  field  studies  and  collections  are  much 
needed  in  the  southern  part  of  the  Great  Basin,  whence  this  form  comes. 


346  GENTJS   ATRIPLEX. 

The  second  group  of  subspecies  consists  of  linearis  and  macropoda,  both  inhabitants  of 
the  arid  Southwest.  They  are  characterized  by  narrower  leaves  and  mostly  smaller 
fruiting  bracts  than  are  found  in  typica,  but  it  will  be  noted  from  the  descriptions  that 
there  is  a  considerable  overlapping  in  these  features.  Forms  intermediate  between 
linearis  and  typica  are  too  numerous  to  justify  the  retention  of  the  former  in  specific  rank. 
The  collections  of  macropoda  are  too  meager  to  permit  of  definite  statements,  but  its  prin- 
cipal character,  the  elongated  stalks  to  the  fruiting  bracts,  is  almost  certain  to  vary  to  a 
considerable  extent  and  not  in  unison  with  other  features. 

ECOLOGY. 

Atriplex  canescens  is  by  far  the  most  widely  distributed  of  all  the  shrubby  species  of 
the  genus.  While  its  original  role  was  evidently  as  a  consociation  of  the  Basin  sagebrush 
association,  it  occurs  in  the  mixed  prairie  of  the  western  Dakotas  and  Nebraska,  the 
desert  plains  and  desert  scrub  of  the  Southwest,  and  in  the  Coastal  sagebrush  of  Cali- 
fornia. Though  it  has  a  wide  range  of  adaptability,  growing  from  Sarcobatus  flats  to 
grassland  valleys  with  practically  no  alkali,  it  is  usually  found  in  soils  with  a  salt-content 
ranging  from  0.03  to  0.10  per  cent.  In  the  Basin  sagebrush  association,  A.  canescens 
typically  occupies  well-drained  valleys,  while  in  the  Coastal  sagebrush  it  runs  from  the 
edge  of  alkaline  depressions  well  into  the  mixture  of  Artemisia,  SaMa,  Eriogonum,  and 
Pentstemon,  or  occurs  in  peculiar  forms  along  the  seashore  back  of  the  strand.  It  is 
frequent  in  alkaUne  flats  in  desert  plains  and  scrub  from  western  Texas  to  the  Mojave 
Desert,  often  associated  with  A.  polycarpa,  and  less  often  with  lentiformis.  It  is  a  regu- 
lar associate  with  Prosopis  on  the  dunes  formed  by  the  latter,  from  the  White  Sands  of 
New  Mexico  to  the  dunes  of  the  Imperial  Valley,  though  in  itself  it  is  a  poor  dune-former. 
This  universal  tendency  to  form  a  subclimax  that  is  post-climax  in  nature  is  further  seen 
in  the  Ohgocene  bad-lands  of  the  Black  Hills  region,  where  it  is  frequent  in  ravines  and 
on  more  stable  slopes . 

USES. 

This  species  is  exceptional  in  the  genus  for  its  economic  value.  Its  vigorous  growth 
and  masses  of  wing-fruits  give  it  considerable  worth  as  an  ornamental  in  somewhat  alka- 
line soils,  where  it  also  may  be  grown  into  a  serviceable  hedge.  Its  chief  importance, 
however,  is  for  grazing.  It  is  the  most  palatable  of  the  shrubby  species,  at  least,  and 
possesses  unique  value  during  drought  periods  when  the  grass  crop  is  short.  It  has  been 
successfully  introduced  into  the  desert  plains  at  Tucson,  Arizona,  and  can  probably  be 
grown  with  even  greater  success  in  the  other  associations  of  the  grassland  formation.  Its 
value  in  the  Southwest  has  been  discussed  by  Griffiths  (U.  S.  Dept.  Agr.  Bur.  Plant 
Ind.  Bull.  4:17,  1901).  As  a  form  of  insurance  against  recurrent  drought  periods  it 
deserves  a  permanent  place  in  grazing  economy. 

Reports  that  the  herbage  is  poisonous  to  stock  have  led  to  a  detailed  chemical  and 
experimental  investigation  by  the  Nevada  Experiment  Station,  the  complete  results  of 
which  are  not  yet  ready  for  publication.  Analyses  made  by  Miller,  the  chemist  at  this 
station,  reveal  the  presence  of  saponin  in  large  amounts,  of  pectins,  and  of  glucosides.  It 
is  believed  by  Miller  that  the  glucosides  are  not  injurious,  but  that  poisoning,  if  it  occurs, 
is  due  to  the  saponins.  Experiments  on  sheep  indicate  that  the  plants  are  sometimes 
harmless,  while  in  other  cases  death  results.  It  is  probable  that  the  high  value  of  Atri- 
plex canescens  when  browsed  under  normal  conditions  and  when  mixed  with  other  feed 
much  more  than  offsets  its  possibly  injurious  effects  in  certain  cases. 

The  seeds  of  this  and  other  shrubby  species  are  ground  into  meal  by  the  Indians  and 
mixed  with  other  flours  in  the  preparation  of  food.  The  pollen  has  been  found  to  be  a 
cause  of  hay-fever  in  a  few  cases  and  therefore  is  used  in  the  preparation  of  immunization 
extracts. 


College 


Explanations  of  Plates  36  to  58,  Genus  Atriplex. 


Plate  36. 

Atriplex  hortensis.  (Drawn  from  fresh  material  from 
Logan,  Utah,  except  figures  4  and  5,  these 
from  a  specimen  from  Austria,  7174  UC.) 

(1)  Leaf  and  part  of  pistillate  inflorescence,  X  1. 

(2)  Fruiting  bracts,  X  2. 

(3)  Vertical  section  of  the  seed,  showing  the  inferior 

position  of  the  radicle,  X  16. 

(4)  Summit  of  stem  with  staminate  inflorescence, 

X  1. 

(5)  Staminate  flower,  X  16. 
Plate  37. 

Atriplex  patula  hastala. 

(1)  Inflorescence  and  upper  leaves,  X  1.     (Drawn 

from  fresh  material  from  Logan,  Utah.) 

(2)  Portion   of  stem   with   an   average   leaf,  X  1. 

(From  the  same  plant  as  1.) 

(3)  Staminate   flower,  X  16.      (From    San    Fran- 

cisco Bay,  California.) 

(4)  Fruiting  bracts,  X  2.     (From   San   Francisco 

Bay,  California.) 

(5)  Vertical  section  of  the  seed  showing  the  inferior 

position  of  the  radicle,  X  16.  (From  the 
same  material  as  1.) 

(6)  Inflorescence   and   upper   leaves   of   a   minor 

variation  {carnosa),  X  1.  (Drawn  from  fresh 
material  from  Solano  County,  California.) 

(7)  Portion  of  stem  with  leaves,  X  1.     (From  the 

same  plant  as  6.) 
Atriplex  patula  typica.     (Material  from  San  Francisco 
Bay,  California.) 
,    (8)  Part  of  inflorescence,  with  typical  leaves,  XI. 

(9)  A  pair  of  fruiting  bracts  as  seen  from  above, 

the  seed  visible  in  the  opening;  X  2. 
(10)  Fruiting   bracts,    showing   gradation   in   size, 
dentations,  and  sculpturing;  X  2. 
Plate  38. 
Atriplex  rosea.    (Drawn  from  fresh  material  and  photo- 
graphs from  Logan,  LUah,  and  from  Byron, 
California.) 

(1)  Upper  portion  of  plant  showing  leaves  and 

inflorescence,  X  1. 

(2)  Portion  of  stem  mth  lower  leaf,  X  1. 

(3)  Sketches  to  show  variation  in  habit;  all  grada- 

tions from  simple-stemmed  to  bushy  plants 
are  common;  small  sketches,  X  0.1,  bushy 
plant  X  0.02. 

(4)  Staminate  flower,  X  16. 

(5)  Fruiting  bracts  showing  variation  on  a  single 

plant,  X  2. 

(6)  Vertical  section  of  seed  showing  the  ascending 

position  of  the  radicle,  X  16. 
Atriplex  maritima.     (Material  from  New  Brunswick, 
Blake  5692,  Gr.) 

(7)  Upper  portion  of  stem  with  leaves,  X  1. 

(8)  A  series  of  three  fruiting  bracts,  X  2. 
Atriplex  talarica.     (Material  from  Pensacola,  Florida, 

110231  UC,  the  bracts  from  Camden,  New 
Jersey,  US.) 

(9)  Branch  showing  the  characteristic  pinnatifid 

leaves  and  the  inflorescence,  X  1. 

(10)  Fruiting  bract,  X  2. 

(11)  Fruiting  bract  with  cristate  appendages,  X  2. 
Plate  39. 

Atriplex   semihaccata.      (Drawn    from    fresh   material 
of  plants  growing  in  California.) 
(1)  Branches  showing  leaves  and  fruiting  bracts 
and    the    short    staminate    clusters;    stems 
trailing;  X  1. 


Plate  39 — continued. 

(2)  Staminate  flower,  X  16. 

(3)  Fruiting  bract,  fleshy  and  reddish;  X  2. 

(4)  Vertical  section  of  the  seed  showing  the  inferior 

but  lateral  position  of  the  radicle,  X  16. 
Atriplex  halimoides.    (Material  from  introduced  plants 
collected  in  San  Diego  Countv,   California. 
110273  UC.) 

(5)  Twig  with  leaves  and  small  staminate  clusters, 

X  1. 

(6)  Two  leaves  from  farther  down  the  stem,  X  1- 

(7)  Fruiting  bract,  thick  and  spongious,  X  2. 

(8)  Vertical  section  of  seed  showing  the  inferior 

position  of  the  radicle,  X  16. 
Atriplex  califomica.    (Drawn  from  fresh  material  from 
Ventura  County,  California.) 

(9)  Spray  showing  the  numerous  fruiting  bracts 

in  the  axils  of  the  crowded  leaves,  prostrate 
from  a  fusiform  taproot,  X  1. 

(10)  Staminate  flower,  X  16. 

(11)  Fruiting  bracts,  united  only  at  very  base;  X  2. 

(12)  Vertical  section  of  seed  showing  the  inferior 

position  of  the  radicle,  X  16. 
Plate  40. 

Atriphx   phyUostegia.     (Drawn    from    fresh    material 
from  north  of  Reno,  Nevada.) 

(1)  Upper  portion  of  plant  showing  characteristic 

leaves,  fruiting  bracts,  and  staminate  clusters; 
X  1.     The  plants  are  strictly  erect. 

(2)  Staminate  flower,  X  16. 

(3)  Fruiting  bracts,  X  2. 

(4)  Vertical  section  of  seed  showing  the  superior 

position  of  the  radicle,  X  16. 

(5)  Fruiting  bracts  with  unusual  appendages,  X  2. 

(From  the  type  of  A.  draconis,  minor  varia- 
tion 2.) 
Atriplex   dioeca.     (Material    from    Johnson    County, 
Wyoming,  51442  UC). 

(6)  Branch  showing  the  very  smooth  leaves  and 

the  staminate  inflorescence,  the  minute 
fruiting  bracts  hidden  in  the  axils  of  the 
leaves;  X  1. 

(7)  Staminate  flower,  X  16. 

(8)  Fruiting  bracts,  X  2. 

(9)  Vertical    section    of    the    seed    showing    the 

superior  position  of  the  radicle,  X  16. 
Atriplex  monilifera.     (Drawn  from  type  material,  Gr.) 

(10)  Leafy  branch,  probably  prostrate;  X  1. 

(11)  Staminate  inflorescence,  X  1. 

(12)  Staminate  flower,  X  16. 

(The   pistillate   flowers   of   this   species   are 
unknown.) 
Plate  41. 

Atriplex  tularensis.     (Drawn  from  fresh  material  from 
the  type  locality.) 

(1)  Upper  portion  of  a  large  plant  showing  the 

leaves  and  the  virgate  inflorescence,  X  1. 

(2)  An  entire  smaller  plant,  X  1. 

(3)  Vertical    section    of    the    seed    showing    the 

superior  position  of  the  radicle,  X  16. 

(4)  A  series  of  four  fruiting  bracts,  all  from  the 

same  plant  as  illustrated  in  fig.  1 ;  X  2. 

(5)  A  series  of  three  fruiting  bracts  taken  from 

plants  growing  near  the  ones  shown  in  figs.  1 
and  2,  X  2. 

(6)  Staminate  flower,  X  16. 

Atriplex  tenuissima.     (Drawn  from  specimens  of  the 
type  collection,  206831  UC,  except  fig.  IL) 

(7)  Branch  with  leaves  from  type  collection,  X  1. 

(8)  A  series  of  four  bracts  from  a  single  plant,  X  2. 


Explanations  of  Plates  36  to  58,  Genus  Atriplex. 


Plate  41 — continued. 

(9)  Vertical    section    of    the    seed    showing    the 
superior  position  of  the  radicle,  X  16. 

(10)  Staminate  flower,  X  16. 

(11)  Branch  with  leaves  from  the  type  of  a  minor 

variation,  X  1.  (A.  greenei,  from  Rock 
Springs,  Wyoming,  78605  R.  For  a  com- 
parison between  the  bracts  of  this  form  and 
t>'pical  tenuissima  see  fig.  34,  p.  274.) 
Atrij^ex  pusilta.  (Drawn  from  fresh  material  from 
Wells,  Nevada.) 

(12)  Entire  plant  of  slightly  less  than  the  average 

size,  X  1. 

(13)  Staminate  flower,  X  16. 

(14)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 

(15)  Fruiting   bract,  X  2.     As   far   as   known   the 

bracts  are  always  of  this  shape  and  devoid 
of  dentations  and  appendages. 
Atripkx  parishi. 

(16)  Branch  with  mostly  opposite  but  a  few  alter- 

nate   leaves,  X  1-     (Material    from    Orange 
County,  California,  111236  UC.) 

(17)  Two  bracts  from  the  same  plant  as  16,  X  2. 

(18)  Branch   with  alternate  leaves,  X  1.     (Drawn 

from  fresh  material  from  Chowchilla,  Cali- 
fornia.) 

(19)  Three  fruiting  bracts  from  the  same  plant,  X  2. 

(20)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16.     (Drawn  from 
one  of  the  bracts  shown  m  19.) 

(21)  Staminate  flower  from  the  same  plant,  X  16. 

(22)  Two  bracts  of  a  single  pair,  X  16.     (Drawn 

from    the    type   of   minor   variation    1,    A. 
depressa.) 

(23)  Habit  sketch  of  a  plant  growing  in  heavy, 

alkaline,  cracked  clay  soil  in  Glenn  County, 
California. 
Plate  42. 
Atriplex    graciliflora.     (Drawn    from    fresh    material 
from  Book  Cliffs,  eastern  Utah,  205346  UC, 
except  fig.  4.) 

(1)  One   of   the   ascending   branches,    terminated 

by  a  staminate  inflorescence;  X  1- 

(2)  Twig  showing  more  clearly  the  fruiting  bracts, 

these  distinguished  from  the  leaves  by  the 
heavier  shading  in  the  center;  X  1. 

(3)  A  series  of  three  immature  bracts  showing  a 

gradation    towards    the    truncata    type    of 
bract,  X  2. 

(4)  A  series  of  three  bracts  with  the  characteristic 

suborbicular    outline,  X  1.  '  (Material    from 
Price,  Utah,  Hb.  Jones.) 

(5)  Vertical    section    of    the    seed    showing    the 

superior  position  of  the  radicle,  X  16. 

(6)  Staminate  flower,  X  16. 

Alrijdex  rvolfi.  (Drawn  from  fresh  material  from 
Grand  Junction,  Colorado,  the  bracts  and 
seed  from  the  type  specimen.) 

(7)  Branch  showing  the  numerous  twigs  and  the 

leaves,  X  1. 

(8)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 

(9)  Two  fruiting  bracts,  X  2. 

Atriplex  truncata.  (Drawn  from  fresh  material  from 
Longmont,  Colorado.) 

(10)  Entire  plant  of  a  moderately  strict  form,  X  1. 

(11)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 

(12)  Two  fruiting  bracts,  X  2. 


Plate  43. 

Atriplex  saccaria. 

(1)  Branch   showing    leaves,    appendaged   bracts, 

and   staminate   inflorescence;  X  1.     (Drawn 
from  fresh  material  from  Green  River,  Utah.) 

(2)  Twig  with  nearly  flat  leaves,  X  1.     (Material 

from  Marysvale,  ITtah,  159008  UC.) 

(3)  Portion  of  branch  with  only  moderately  appen- 

daged   bracts,  X  2.     (Material    from    Chal- 
cedony Park,  Arizona,  205283  UC.) 

(4)  Fruiting   bract  from   the  same   collection   as 

fig.  3;  most  bracts  on  some  plants  are  of  this 
form,  suggestive  of  A.  truncata;  X  2. 

(5)  Fruiting  bract  from  same  plant  as  fig.  1,  X  2. 

(6)  Staminate  flower  from  the  same,  X  16. 

(7)  Vertical    section    of    a    seed    from    the    same 

showing  superior  position  of  radicle,  X  16. 
Atriplex  argentea  typica.     (Drawn  from  material  from 
Longmont,  Colorado,  except  as  indicated.) 

(8)  Branch    showing    the    short-petioled     upper 

leaves  and  the  fruiting  bracts,  X  1. 

(9)  Vertical    section    of    the    seed    showing    the 

superior  position  of  the  radicle,  X  16. 

(10)  A  series  of  four  fruiting  bracts,  all  from  the 

same   plant  showing  variation   in   margins, 
appendages,  and  length  of  stalk;  X  2. 

(11)  Staminate  flower,  X  16. 
Atriplex  coronata. 

(12)  Branch  of  a  garden  plant  grown  at  Berkeley 

California;  X  1. 

(13)  Portion  of  twig  and  leaf  of  the  type  specimen 

(Gr),  X  1. 

(14)  Series  of  three  fruiting  bracts,  X  2.     (Material 

from  south  of  Dos  Palos,  CaUfomia,  205345 
UC.) 

(15)  Staminate  flower  from  the  same  plant  as  fig. 

12,  X  16. 

(16)  Vertical  section  of  one  of  the  bracts  showing 

the  superior  position  of  the  radicle,  X  16. 

(17)  Two    fruiting    bracts    with    strongly    cristate 

appendages,  X  2.     (From  the   type  of  var. 
notatior,  minor  variation  1,  Hb.  Jepson.) 
Atriplex  cordulata. 

(18)  A  virgate  branch  showing  the  closely  sessile, 

cordate    leaves:  X  1.     (Drawn    from    fresh 
material  from  Chowchilla,  California.) 

(19)  A   small,   unbranched   plant;  X  1.     (Material 

from  Volta,  Cahfornia,  204515  UC.) 

(20)  Staminate  flower  from  the  same  collection  as 

fig.  19,  X  16. 

(21)  Vertical  section  of  a  bract  from  the  same  col- 

lection showing  the  superior  position  of  the 
radicle,  X  16. 

(22)  Series  of  three  fruiting  bracts  from  the  same 

collection,  X  2. 

(23)  Series  of  three  fruiting  bracts  from  the  type 

specimen  (Hb.  Jepgon),  X  2. 
Plate  44. 
Atriplex  argentea  expansa.     (All  drawings  are  from  a 
single  plant  collected  in  the  Livermore  Valley, 
middle  western  California,  except  fig.  19.) 

(1)  A  leafy  fruiting  branch  showing  the  closely 

sessile  upper  leaves,  X  1. 

(2)  Habit  of  the  mature  plant  growing  in  a  fallow 

field,  X  0.1. 

(3)  to  (8)  A  series  of  leaves  selected  to  show  the 

range  of  variation  from  the  lower  to  the  upper 
on  a  single  plant,  X  1. 
(9)  Vertical  section  of  the  seed  showing  the  superior 
position  of  the  radicle,  X  16. 


Explanations  of  Plates  36  to  58,  Genus  Atmplex. 


Plate  44 — continued. 

(10)  Twig  showing  fruiting  bracts  mixing  with  a 

few  staminate  flowers,  X  2. 

(11)  Inflorescence  of  staminate  flowers  only,  X  2. 

(12)  Staminate  flower  taken  from  the  inflorescence 

shown  in  fig.  11,  X  16. 

(13)  to  (18)  A  series  of  fruiting  bracts  selected  to 

show  range  of  variation  on  one  plant,  X  2. 
(19)  Seedling  grown  from  seed    collected  with  the 
plant  from  which  the  other  drawings  were 
made,  to  show  the  opposite  lower  leaves. 
Plate  45. 
Atriplex  powelli.     (Drawn  from   fresh   material  and 
photographs  from  Green   River,  Utah,  the 
bracts  from  near  Grand  Junction,  Colorado.) 

(1)  Upper  portion  of  a  plant  almost  entirely  pistil- 

late, showing  the  three-ribbed  leaves;  X  1. 

(2)  Branch   of   the   inflorescence   from   a   mostly 

staminate  plant,  X  1. 

(3)  Leaf  from  a  pistillate  plant  showing  large  size 

and   characteristic   venation,   bottom   view; 
X  1. 

(4)  Sketch  of  habit  of  a  staminate  plant,  XO.08. 

(5)  Sketch  of  habit  of  a  pistiUate  plant,   X  0.08. 

(6)  Staminate  flower,  X  16. 

(7)  A  series  of  three  fruiting  bracts  showing  the 

characteristic  transverse  terminal  lobe,  X  2. 

(8)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 
Atnplex  leucophylla.    (Drawn  from  fresh  material  and 
photograph  from  Ventura,  Cahfornia.) 

(9)  An  ascending  branch,  X  1. 

(10)  Tip  of  a  leafy  shoot  showing  the  staminate 

clusters  and  upper  bracts,  X  1. 

(11)  Habit  sketch  of  a  plant,  the  base  covered  by 

blown  sand,  X  0.8. 

(12)  Staminate  flower,  X  16. 

(13)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 

(14)  A  series  of  six  bracts,  all  from  the  plant  shown 

in  fig.   11,  showing  variation  in  shape  and 
sculpturing;  X  2. 
Plate  46. 
Atriplex  pentandra  arenaria.     (Drawn  from  material 
from    Westport,    Massachusetts,    7151    UC, 
except  the  habit  sketch.) 

(1)  Portion  of  branch  showing  leaves,  bracts,  and 

a  short  terminal  staminate  inflorescence;  X  1. 

(2)  Habit  sketch  of  plant,  the  base  covered  with 

blown  sand;  X  0.08.    (From    a    photograph 
taken  at  Nahant,  Massachusetts.) 

(3)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 

(4)  Fruiting   bract   with   a    pair   of   crested   ap- 

pendages, X  2. 

(5)  Fruiting  bract  from  the  same  plant,  the  faces 

smooth;  X  2. 

(6)  Staminate  flower,  X  16. 

Atriplex  pentandra  muricata.    (Material  from  Coahuila, 
110219  UC.) 

(7)  Portion  of  branch  with  leaves  and  bracts,  X  1. 

(8)  Two  fruiting  bracts  from  the  same  branch,  X  2. 
Atriplex  pentandra  typica. 

(9)  Portion  of  branch  showing  leaves  and  bracts 

from  a  plant  collected  in  Cuba,  X  1.    (.Britton 
and  Wilson  53,  NY.) 

(10)  Fruiting  bract  from  the  same  branch,  X  2. 

(11)  Fruiting  bract  from  plant  collected  in  Curagao, 

X  2.     (Britton  and  Shafer  2926  NY.) 

(12)  Two  leaves  from  the  type  of  A.  teiana  (=  A. 

pentandra  minor  variation  16),  X  1. 


Plate  46 — continued. 

(13)  Two  bracts  from  the  same  plant  as  12,  X  2. 
Atriplex  elegans  typica.     (Drawn  from  fresh  material 

from   Yuma,   Arizona,   except  as  otherwise 
indicated.) 

(14)  Branches  heavily  laden  with  fruiting  bracts, 

X  1. 

(15)  Habit  sketch  of  a  normally  developed  plant, 

X  0.07. 

(16)  Staminate  flower,  X  16. 

(17)  Fruiting  bracts,  X  2. 

(18)  Cluster  of  fruiting  bracts  and  an  exceptionally 

dentate  leaf,  X  1.     (Material  from  Durango, 
110218  UC.) 

(19)  Two  bracts  from  the  cluster  shown  in  18,  X  2. 

(20)  Vertical    section    of    the    seed    showing    the 

superior  position  of  the  radicle,  X  16. 

(21)  Branch  of  a  plant  with  crested  bracts,  X  1. 

(Minor  variation  1,  var.  thronberi.    Material 
from  Santa  Cruz  Valley,  Arizona,  7216  UC.) 

(22)  Fruiting  bracts  from  branch  shown  in  21,  X  2. 
Atriplex  elegans  fasciculata.      (Material  from  Borregos 

Springs,  California,  110270  UC.) 

(23)  Tip  of  leafy  fruiting  shoot,  X  1. 

(24)  Fruiting  bract  showing  the  minutely  dentate 
X2. 


Plate  47. 
Atriplex  bracteosa.    (Drawn  from  fresh  material  from 
Manteca,    California,    except    as    otherwise 
noted.) 

(1)  Branches  showing  leaves,  fruiting  bracts,  and 

staminate  inflorescence;  X  1. 

(2)  Typical  leaf  showing  the  characteristic  shape 

and  dentation,  X  1.    (Material  from  Tulare, 
California,  14100  UC.) 

(3)  Staminate  flower,  X  16. 

(4)  A  series  of  three  fruiting  bracts,  X  2. 

(5)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 
Atriplex  ivrighti.    (Drawn  from  material  from  Tucson, 
Arizona,  128543  UC.) 

(6)  Portion  of  inflorescence  showing  fruiting  bracts 

on    a    lower    branch    and    long    staminate 
branches  above,  X  1. 

(7)  Leaf  from  lower  down,  X  1. 

(8)  Staminate  flower,  X  16. 

(9)  Series  of  three  bracts,  X  2. 

(10)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 
Atriplex    linifolia.       (Drawn    from     material    from 
Durango,  110220  and  110228  UC.) 

(11)  Upper  portion  of  staminate  inflorescence  with 

upper  leaves,  X  1. 

(12)  Upper  portion  of  a  chiefly  pistillate  inflorescence 

but  with  some  staminate  glomerules  above; 
from  another  plant;  X  1. 

(13)  Staminate  flower,  X  16. 

(14)  A  series  of  three  fruiting  bracts,  X  2. 

(15)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 
Plate  48. 
Atnplex   microcarpa.     (Drawn    from    material    from 
Laguna,  Orange  County,  California.) 

(1)  Branch  showing  leaves^  fruiting  bracts,   and 

staminate  clusters;  X  1. 

(2)  Fruiting  bract,  X  2. 

(3)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 

(4)  Staminate  flower,  X  16. 


Explanations  of  Plates  36  to  58,  Genus  Atriplex. 


Plate  48 — continued. 

Atriplex  fruticulosa.  (Drawn  from  a  living  specimen 
grown  at  Berkeley,  California,  the  original 
seed  from  the  San  Joaquin  Valley,  except  9.) 

(5)  An  ascending  branch  showing  leaves,  fruiting 

bracts,  and  staminate  clusters,  X  1. 

(6)  Staminate  flower,  X  16. 

(7)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 

(8)  A  series  of  three  fruiting  bracts,  X  2. 

(9)  A  series  of  three  fruiting  bracts  from  the  type 

specimen,  X  2.     (Herb.  Jepson.) 
Atriplex    eoulteri.     (Drawn    from   material  from  La 
JoUa,  San  Diego  County,  California.) 

(10)  A  branch  showing  the  leaves,  fruiting  bracts, 

and  staminate  clusters,  X  1. 

(11)  Staminate  flower,  X  16. 

(12)  Two  fruiting  bracts,  X  2. 

(13)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 
Plate  49. 
Atriplex    decumbens.     (Drawn    from    fresh    material 
from  San  Diego  County,  California.) 

(1)  Branch  of  a  prostrate  pistillate  plant,  X  1. 

(2)  A  series  of  three  fruiting  bracts,  X  2. 

(3)  Vertical   section    of   the   ovary    showing   the 

superior  position  of  the  radicle,  X  16. 

(4)  Branch  of  a  staminate  plant,  X  1. 

(5)  Staminate  flower,  X  16. 

Atriplex  malarrwrensis.  (Material  from  southwestern 
Texas,  Palmer  11601  US.) 

(6)  Tip  of  a  branch  from  a  pistillate  plant,  X  1. 

(7)  Fruiting  bracts,  X  2. 
Atriplex  barclayana  typica. 

(8)  Branch  and  inflorescence  of  a  staminate  plant, 

X  1.     (Material  from  Estaban  Island,  Gulf 
of  California,  Johnston  3190  UC.) 

(9)  Staminate  flower  from  8,  X  16. 

(10)  Branch  of  a  pistillate  plant  with  bracts,  X  1. 

(Material  from  Isla  Partida,  Gulf  of  CaU- 
fomia,  Johnston  SS28,  UC.) 

(11)  Three   thick   fruiting   bracts   of   typical   bar- 

clayana, X  2.     (From  the  same  plant  as  10.) 

(12)  Two  fruiting  bracts,  compressed  as  in  subsp. 

palmeri;  X  2.     (From    the    same    plant    as 
10  and  11.) 

(13)  Vertical  section  of  a  typical  thick  bract,  X  16. 
Atriplex  barclayana  lurida.     (From  type,  110251  UC.) 

(14)  Leaves  showing  characteristic  dentation,  X  1. 

(15)  A  series  of  three  fruiting  bracts,  X  2. 
Atriplex  barclayana  sonorae.     (Drawn  from  the  type 

material,  635444  US.) 

(16)  A  series  of  three  fruiting  bracts,  X  2. 
Atriplex    barclayana    dilatata.     (Material    from    San 

Benito  Island,  Anthony  269  UC.) 

(17)  A  series  of  four  fruiting  bracts,  X  2. 
Plate  50. 

Atriplex  obovata.  (Drawn  from  fresh  material  from 
northwestern  New  Mexico.) 

(1)  Branch  of  staminate  plant,  X  1. 

(2)  Staminate  flower,  X  16. 

(3)  Branch  of  pistillate  plant,  X  1. 

(4)  A  leafy  sterile  shoot,  X  1. 

(5)  Fruiting  bract,  X  2. 

(6)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 

(7)  Habit  sketch  of  a  staminate  plant,  X  0.12. 


Plate  50 — continued. 

(8)  Habit  sketch  of  a  pistillate  plant,  X  0.12. 
Atriplex     acanthocarpa.     (Staminate     material     from 

San  Luis  Potosi,  110337  UC;  pistiUate 
material  from  Torreon,  Coahuila,  1 10223 UC.) 

(9)  Staminate  inflorescence,  X  1. 

(10)  Staminate  flower,  X  16. 

(11)  Branch  of  a  pistillate  plant,  X  1. 

(12)  Fruiting  bract,  X  2. 

(13)  Another  fruiting  bract  from  the  same  plant 

but  showing  more  laciniate  margins  and 
appendages,  X  2. 

(14)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 
Plate  51. 
Atriplex  nultalli  gardneri.     (Drawn  from  fresh  material 
from  Point  of  Rocks,  Wyoming.) 

(1)  Erect  leafy  stem  with  fruiting  bracts,  X  1. 

(2)  Tip  of  a  branch  from  a  staminate  plant,  X  1. 

(3)  Staminate  flower,  X  16. 

(4)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 
Atriplex  nuttalli  typica.     (Drawn  from  fresh  material 
from  Green  River,  Utah,  and  Grand  Junction, 
Colorado.) 

(5)  Leaf  and  fruiting  stem  of  pistillate  plant,  X  1. 

(6)  Branch  of  another  plant  showing  a  staminate 

inflorescence,  X  1. 

(7)  Habit  sketch,  X  0.1. 

(8)  An  unusual  type  of  fruiting  bract,  representing 

a  primitive  form;  X  2. 

(9)  A    common    type    of    bract    with    numerous 

cristate  appendages,  X  2. 

(10)  Staminate  flower,  X  16. 

Atriplex  corrugata.  (Drawn  from  material  and  photo- 
graphs from  Green  River,  Utah,  the  staminate 
inflorescence  from  Gunnison  River,  Colorado.) 

(11)  Leafy  branches  and  spikes  of  fruiting  bracte, 

X  1. 

(12)  Inflorescence  of  a  staminate  plant,  X  1. 

(13)  Staminate  flower,  X  16. 

(14)  Fruiting  bracts  showing  the  flat-appendaged 

faces  and  the  broad  terminal  lobe,  X  2. 

(15)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 

(16)  Habit  sketch,  X  0.1. 
Plate  52. 

Atriplex  polycarpa.  (Drawn  from  fresh  material 
from  Tehachapi  Pass,  Calif .,  except  3, 6,  and  7.) 

(1)  Branch  of  a  pistillate  shrub,  the  leaves  still 

adhering;  X  1. 

(2)  End  of  a  branch  showing  the  pistillate  inflores- 

cence, X  1. 

(3)  Staminate     flower,  X  16.        (Material     from 

Bakersfield,  California,  7097  UC.) 

(4)  Vertical    section    of    the    seed    showing    the 

unusual  basal  position  of  the  plumule,  the 
three  embryos  examined  all  exhibited  this 
peculiarity;  X  16. 

(5)  A  series  of  five  fruiting  bracts,  the  lower  row 

smooth,  from  one  plant,  the  other  two  from 
another  plant;  X  2. 

(6)  A  series  of  three  fruiting  bracts  from  the  type 

specimen  of  A.  curvidens  (minor  variation 
3),  X  2. 

(7)  A  series  of  three  fruiting  bracts  from  Tucson, 

Arizona,  (128246  UC)  of  a  form  resembling 
curvidens;  X  2. 


Explanations  of  Plates  36  to  58,  Genus  Atriplex. 


Plate  52 — continued. 
Alriplex  julacea.     (Drawn   from   material   from   San 
Bartolome   Bay,    Lower   California,    110297 
UC.) 

(8)  Twig  of  pistillate  plant,  X  1. 

(9)  Leaf  showing  the  sessile  hastate  base,  X  8. 

(10)  Two  fruiting  bracts,  X  2. 

(11)  Vertical  section  of  the  seed  showing  the  superior 

position  of  the  radicle,  X  16. 
Plate  53. 

Atriplex  hymenelytra. 

(1)  Branch  of  a  pistillate  shrub  showing  the  char- 

acteristic foliage,  the  leaves  silvery  white 
with  a  dense  scurf,  X  1.  (Drawn  from  fresh 
material  from  Yuma,  Arizona.) 

(2)  Habit  sketch  of  normal  mature  plant  as  it  grows 

in  alkaline  desert  gravel  at  Yuma,  X  0.066. 

(3)  Inflorescence  of  a  staminate  plant,  X  1.     (Ma- 

terial from  Inyo  County,  Calif.,  110265  UC.) 

(4)  Staminate  flower,    X    16.     (Drawn  from  the 

same  material  as  3.) 

(5)  A  series  of  four  fruiting  bracts,  X  2.     (Drawn 

from  the  same  material  as  6.) 

(6)  Portion  of  a  pistillate  inflorescence  showing  the 

fniiting  bracts,  X  1.  (Material  from  Spht 
Mountain,  California,  110314  UC.) 

(7)  Vertical  section  of  the  seed  showing  the  supe- 

rior position  of  the  radicle,   X   16.     (From 
the  same  material.) 
Plate  54. 

Atriplex  lentiformis  breweri. 

(1)  Leafy  fruiting  inflorescence  of  a  plant  chiefly 

pistillate  but  with  a  few  staminate  glomerules, 
X  1.  (Drawn  from  fresh  material  from  south 
of  Hollister,  California.) 

(2)  Habit  sketch  of  a  shrub  growing  near  Ventura, 

California,  just  back  of  the  beach;  X  0.02. 
Many  of  the  plants  are  more  symmetrical  and 
round-topped. 

(3)  Three  types  of  leaves  common  in  coast  plants, 

X  1. 

(4)  Vertical  section  of  the  seed  with  inside  view  of 

the  bract,  X  16. 

(5)  Fruiting  bract  from  plant  shown  in  fig.  1,  X  2. 

(6)  Two  fruiting  bracts  from  a  single  plant,  the 

margins  crenulate  as  in  typica;  X  2.  (Ma- 
terial from  Ventura  County,  California.) 

(7)  Two  fniiting  bracts  from  another  plant,  X  2. 

(Material  from  Ventura  County.) 

(8)  Staminate   flower,    X    16.     (From   the  inflor- 

escence shown  in  fig.  10.) 

(9)  Portions  of  inflorescence  showing  a  mixing  of 

the  staminate  and  pistillate  flowers,  X  1. 
(Drawn  from  fresh  material  from  Ventura 
County.) 

(10)  Staminate  inflorescence  of  a  plant  growing  near 

the  one  shown  in  fig.  1,  X  1. 
Atriplex  lentiformis  typica. 

(11)  Leaf,  X  1.     The  shape  is  often  similar  to  that 

of  fig.  3. 

(12)  Two  bracts  from  the  same  plant  showing  the 

small  size  and  characteristic  margins  of 
typica,  X  2.  (Material  from  south  of  Bak- 
ersfield,  California.) 

(13)  A  bract  from  a  plant  in  the  area  of  typica  but 

with  the  smooth  margins  of  breweri,  X  2. 
(Material  from  south  of  Bakersfield,  Calif.) 


Plate  55. 

Atriplex  lentiformis  griffithsi.  (Drawn  from  the  type 
specimen,  NY.) 

(1)  Twig  with  fruiting  bracts,  X  1.     The  stems  are 

angled  as  in  subspecies  torreyi. 

(2)  Two  fruiting  bracts,  X  2. 

Alriplex  lerdiformis  torreyi.  (Drawn  from  fresh 
material  from  the  Truckee  River  Valley, 
near   Vista,    Nevada.) 

(3)  A  leafy  inflorescence  from  a  staminate  plant  at 

the  height  of  the  flowering  season,  X  1. 

(4)  A  naked  inflorescence  from  a  pistillate  plant 

taken  late  in  the  season,  X  1. 

(5)  Cross-section    of    stem    showing    the    raised 

angles,  X  4. 

(6)  Habit  sketch  of  a  pistillate  shrub,  X  0.02. 

(7)  Staminate  flower,  X  16. 

(8)  Vertical  section  of  the  seed  showing  the  supe- 

rior radicle,  X  16. 

(9)  Fruiting  bracts,  X  2. 
Plate  56. 

Atriplex  confertifolia. 

(1)  A  nearly  leafless  spiny  branch  in  winter  con- 

dition, X  1.  (Material  from  Antelope  Val- 
ley, California.) 

(2)  An  exceptionally  leafy  branch  of  a  pistillate 

plant  in  early  summer  condition,  growing  in 
fairly  good  soil,  X  1.  (Material  from  wes- 
tern Idaho.) 

(3)  A  less  foliaceous  branch  from  a  plant  in  dry 

soil,  X  1.     (Material  from  southern  Idaho.) 

(4)  Branch    of   a   staminate    plant   showing   the 

glomerules,  X  1.  (Drawn  from  fresh  ma- 
terial from  Antelope  Valley,  Cahfomia.) 

(5)  Habit  sketch  of  a  normal  plant,  X  0.07. 

(6)  Fruiting  bract,  X  2.     (Material  from  Antelope 

Valley,  Cahfomia.) 

(7)  Fruiting  bract,  X  2.     (Material  from  Naturita, 

Colorado,  205353  UC.) 

(8)  Vertical  section  from  bract  shown  in  7,  X  16. 

(9)  Staminate  flower  from  branch  shown  in  4,  X  16. 

(10)  Leaf  from  the  type  of  A.  collina  (i.  e.,  minor 

variation  1,  p.  339),  X  1. 

(11)  Two  fruiting  bracts  from  the  same  type  as 

10,  X  2. 
Plate  57. 
Atriplex  parryi.     (Drawn  from  material  from  Ante- 
lope  Valley,    California,    the   type   locality, 
7064  and  7113  UC.) 

(1)  Twig  showing  the  spiny   habit  and  cordate 

leaves,  X  1.  The  shape  of  the  shrub  is 
similar  to  that  shown  of  confertifolia  in  plate 
56,  fig.  5. 

(2)  Bracts  showing  variation  in  the  shape  of  the 

base,  X  2. 

(3)  Vertical  section  of  a  seed  showing  the  superior 

position  of  the  radicle,  X  16. 

(4)  Staminate  flower,  X  16. 

Atriplex  spinifera.  (Drawn  from  fresh  material  from 
western  Fresno  Coimty,  Cahfomia,  except 
figs.  8  and  9.) 

(5)  Branch  showing  the  autumn   condition,   the 

leaves  mostly  fallen  but  some  of  the  fruiting 
bracts  still  persisting;  X  1. 

(6)  Branch  showing  the  more  leafy  summer  con- 

dition, X  1. 

(7)  A  fruiting  bract,  X  2. 


Explanations  of  Plates  36  to  58,  Genus  Atmplex. 


Plate  57 — continued. 

(8)  A  fruiting  bract  from  Antelope  Valley,  Cali- 

fornia, showing  the  marked  constriction  at 
base  of  terminal  lobe;  X  2. 

(9)  Vertical    section    of    the    same    showing    the 

superior  position  of  the  radicle,  X  16. 
Plate  58. 

Atriplex  canescens  typica. 

(1)  Fruiting  twig  from  a  shrub  growing  at  Piru, 

Ventura  County,  Cahfornia;  X  1. 

(2)  Portion   of   an   inflorescence   of   a   staminate 

plant  from  the  Argus  Mountains,  California 
(128981  UC);  X  1. 

(3)  Staminate  flower  from  the  same,  X  16. 

(4)  Fruiting  bracts  of  a  plant  from  the  Coronados 

Islands,   Lower   Cahfornia;    X    2.     (195317 
UC,  see  minor  variation  20,  p.  345.) 
(6)  Fruiting  bracts  from  Clark  County,  Nevada 
(176399    UC),    similar    to    those   from  the 
islands:  X  2. 


Plate  58 — continued. 

(6)  A    fruiting    bract    from    southern    California 

(7060  UC),  X  2. 

(7)  A  fruiting  bract  from  plant  shown  in  fig.  1,  X  2. 

(8)  End  view  of  the  same,  X  2. 

(9)  Vertical    section    of    the    same    showing   the 

superior  position  of  the  radicle,  X  2. 

(10)  Habit  sketch  of  a  shrub  at  Winslow,  Arizona; 

X  0.032. 

(11)  A  fruiting  bract  of  var.  Iaci7iiaia,  X  2.     (From 

the  type  collection,   Gr.     See  minor  varia- 
tion 5,  p.  344.) 
Atriplex  canescens  aplera. 

(12)  Three  fruiting  bracts  from  the  type  specimen, 

X  2.     (64938  R.) 
Atriplex  ca7iescens  iiji€ari«.||^(Drawn  from  the  type 
specimen,  Gr.) 

(13)  Fruiting  bracts,  X  2. 

(14)  Leaves  showing  the  narrow  shape,  X  1. 


HALL  AND  CLEMENTS 


Ruth  J.  Powell  del. 


Atriplex  hortensis. 


HALL  AND  CLEMENTS 


Rulh  J.  Powvll  'hi. 


Alriple.x  patiila  haslata.  iigs.  1  to  7.  Atriplex  patiila  t.vpita.  figs,  ii  to  10. 


HALL  AND  CLEMENTS 


Kiilli   J.   Pmrrll  ,1,1. 

Atriplex  rosea,  figs.  1  to  6. 


Oil!         ,  ^   ^\  <1  ^^ 


Atriplex  maritima.  figs.  7  and  8.  Atriplex  tatarica.  figs.  9  to  11. 


HALL  AND  CLEMENTS 


11^      12 

Atriplex  semibaccata,  figs.  1  to  1.  Ati-iplex  halimoides,  figs.  .5  tu  S.  Atriplex  califoinica,  figs.  9  to  12. 


Rulh  J.   Powell  <hl. 


HALL  AND  CLEMENTS 


mm^ 


-^.1 


.10 


12./         11&^!     ^>/ 


Rulh   J.    Powell   .hi. 

Atriplex  phyllostpgia,  figs.  1  to  5.  Atriplex  dioeca,  figs.  6  to  9. 

Atriplex  moniUfera,  figs.  10  and  12. 


HALL  AND  CLEMENTS 


^^■r^MW^ 


# 

> 


AUiplex  tularensis,  figs.  1  t  )  6. 
Atii[il<'\  tPiiuissima,  figs.  7  to  11 


Atriplex  pusilla.  figs.  12  to  15. 
\tiiplex  parishi.  figs.  16  to  2.'5. 


HALL  AND  CLEMENTS 


Rnlh   J.   Powell  <M. 

Atiiplex  graciliflora.  figs.  1  to  6.  Atriplex  wolfi.  figs.  7  to  9.  Atriplex  truncata,  figs.  10  to  1: 


HALL  AND  CLEMENTS 


y^-<fi\i 


'K 


16 


•r  ^'13  I     :«^^ 


Atriplex  saccaria,  figs.  1  to  7. 
Atriplex  aigentea  typica.  figs.  8  to  11. 


Atriplex  coronata.  figs.  12  to  17. 
Atriplex  cordulata.  figs.  18  to  215. 


HALL  AND  CLEMENTS 


f^  n  tp 


Atriplex  argentea  expansa. 


HALL  AND  CLEMENTS 


Rulh  J.  Powell  del. 


Atriplex  powelli.  figs.  1  to 


.\triplpx  leucophylta.  figs.  9  to  It. 


HALL  AND  CLEMENTS 


Atriplex  pentandra  arenaria,  figs.  1  to  6.  Atriplex  pentandra  typica,  figs.  9  to  13. 

Atiiplex  pentandra  muricata.  figs.  7  and  8.  Atriplex  elegans  typica,  figs.  14  to  22. 

Atriplex  elegans  fasciculata.  figs.  2,3  and  24. 


HALL  AND  CLEMENTS 


Hulh  J.  Pmi-eU  del. 

Atriplex  bracteosa,  figs.  1  to 


Atriplex  wrighti,  figs.  6  to  10.         Atriplex  linifolia,  figs.  11  to  15. 


HALL  AND  CLEMENTS 


Rulh  J.   Powell  del. 

Atriplex  micioearpa,  figs.  1  to  \.  Atriplex  fniticulosa,  figs.  5  to  9.  Atriplex  coulteri,  figs.  10  to  13. 


HALL  AND  CLEMENTS 


o  c3^  ^  m 

17   " 


"M  J.  Powell  del. 

Atriplex  decunibens,  figs.  1  to  5. 
Atriplex  barclayana  typica,  figs.  8  to  1.3. 
Atriplex  barclayana  sonorae,  fig.  1 6. 


Atriplex  matamorensis,  figs.  6  and  7. 
Atriplex  barclayana  lurida,  figs.  U  and  15. 
Atriplex  barclayana  dilatata,  fig.  17. 


,^-^il/<. 


Atiiplex  obovata,  figs.  1  to  8.  Atriplex  acanthocarpa,  figs.  9  to  14. 


AND  CLEMENTS 


Atriplex  mittalli  gardnori.  figs.  1  to  4.  Atriplex  mittalli  typica.  figs.  5  to  10.  Atriplex  corrugala,  figs.  11  to  16. 


HALL  AND  CLEMENTS 


Ruth  J.  Powell  M. 


Atriplex  polycarpa,  figs.  1  to  7.  Atiipiex  jnlacea,  figs.  8  to  11. 


MLL  AND  CLEMENTS 


J.  Powdl  del. 


Atiiplex  hynienelytra. 


HALL  AND  CLEMENTS 


Kulh  J.  Pouell  M. 

Atiiplex  lontifoimis  bieweri.  figs.  1  to  10.  Atiiplex  lentiformi.s  typica.  figs.  11  to  13. 


HALL  AND  CLEMENTS 


Kiilh  J.  7'um'pH  del. 


Atriplex  lentiforniis  griflithsi,  figs.  1  and  2. 


Atriplex  lentiforniis  torreyi,  figs.  3  to  9. 


HALL  AND  CLEMENTS 


i,(*  J.  Pmrdl  <M. 


Alriplex  confeitil'i ilia. 


HALL  AND  CLEMENTS 


Ruth   J.   Pmrell  d.L 


Atriplex  parryi,  figs.  1  to  4.  Atriplex  spinifera,  figs.  5  to  9. 


Library 
JJ.  C,  State  Coilegp 


HALL  AND  CLEMENTS 


Rulh  J.   Powell  del. 

Atiiplex  canescens  typica.  figs.  1  to  11.  Atriplex  canescens  aptera.  fig.  ll 

Atiiplex  canescens  finearis.  figs.  13  and  14. 


INDEX. 

(Pages  of  principal  entries  of  accepted  scientific  names  are  in  heavy-face  type.) 


Abronia  maritima,  293 

Abrotanum,  Sect.,  1,  34-38,  46,  49,  55,  135,  156 

Absinthium,  Sect.,  31,  34-36,  46,  106,  107 

vulgare,  34 
Absinthe  Sagewort,  106 
Aconitum,  13 
Adenostoma,  55,  56 
Agropyrum,  132,  206 
AUscale,  19,  40 
Alpine  Sagewort,  112 
Amarantus  palmeri,  305 

watsoni,  320 
Annual  Sagewort,  102 
Antennaria  alpina,  111 

dioeca,  206 
Arenaria  fendleri.  111 
Arrowscale,  266 

Artemisia,  19,  24,  29,  31-156,  346 
abrotanoides,  53 

abrotanum,  38,  41,  46,  48,  49-51,  52,  55,  155 
absinthium,  34,  46-48,  52,  106-108 
alaskana,  46-50,  68,  69 
albula,  81,  85 
androsacea,  65 
angusta,  139 

annua,  46,  47,  50,  101,  102-104 
arachnoidea,  81 
arbuscula,  139,  142 
arctioa,  60,  61 
argophylla,  81 
aromatica,  116-119 
atomifera,  42,  81,  99 
australis,  32,  54,  55 
bakeri,  81,  84,  99 

biennis,  46,  47,  49,  50,  101,  102,  103 
bigelovi,  37,  40,  42,  46,  48-50,  104-106,  135 
bolanderi,  139 
borealis,  123-125 
besseri,  124 
purshi,  124 
spithamsea,  124 
wormskjoldi,  124 
bourgeauana,  123,  124 
brittoni,  81,  82,  95 
californica,  19,  32,  38,  39,  41,  46,  48-52,  53-56, 100, 

131,  156 
campestris,  19,  38,  44,  47,  100,  114,  120-129,  130-133 
borealis,  121,  122,  124-128 
caudata,  121,  122,  125-129 
genuina,  124 
maritima,  129 
pacifica,  121,  122,  124-129 
pycnocephala,  121,  123,  125-129 
spithamaa,  121,  123,  124-129 
typica,  121,  126-129 
camphorata,  61 
camporum,  124,  125 

cana,  19,  37,  41,  42,  47,  48,  135,  U5,  148,  149, 150-153 
viscidula,  151,  152 


Artemisia — Continued. 
canadensis,  124,  125,  127 
candicans,  42,  81 
carruthi,  81,  82,  84,  99 
caudata,  47,  122,  125 

calvens,  125 
cernua,  116 

chamissoniana  saxatilis,  58,  60,  61 
chinensis,  32,  54 
eoloradensis,  82,  99 
columbiensis,  151 
comata,  59,  60 
commutata,  126 
douglasiana,  125 
hookeriana,  125 
richardsoniana,  125 
cooleyae,  61,  67 
cuneata,  82 
cuneifoha,  82 
desertorum,  126 
douglasiana,  125 
hookeriana,  125 
richardsoniana,  125 
scouleriana,  125 
discolor,  39,  74,  82 

incompta,  82 
diversifolia,  82,  85,  87 
domingensis,  29,  82 
douglasiana,  82-84,  92 
dracunculina,  117 
dracunculoides,  116,  117,  119 
brevifolia,  117 
incana,  117 
tenuifolia,  117 
wolfi,  117 
dracunculus,    19,   38,  44,  47,  71,  100,  114,  115-120, 
126,  133,  155 
glauca,  115,  116,  117-119 
typica,  115,  118,  119 
dracunculina,  115,  116,  117,  118 
elatior,  82 
falcata,  82 
filifoUa,  19,  38,  41,  43,  47,  48,  55,  114,  115,  130,  131, 

132 
fischeriana,  53 
vegetior,  53 
floccosa,  73,  82,  99 
flodmani,  83 
foliosa,  53,  54 
forwoodi,  122,  125 

calvens,  125 
transerioides,  44,  46,  47,  49,  50,  68,  69,  70,  72 
frigida,  44,  46,  48,  100,  106,  107,  108-110,  111,  120, 

129,  132,  206,  329 
ghiesbreghti,  83 
glauca,  117 

fastigiata,  117 
globularia,  58,  61-63 
glomerata,  58,  61-63,  65 


348 


Artemisia — Continued. 
gmeliniana,  109 
gnaphalodes,  39,  83,  84 

divereifolia,  83 
gormani,  83 
gracilenta,  73,  83,  99 
gracillima,  117 
graveolens,  83,  85,  87 
groenlandica,  125 
herrioti,  83,  99 
heterophyUa,  42,  58-63,  83 
hookeriana,  83,  84,  92 
hyperborea,  61 
incompta,  82-84,  92,  99 
indica  canadensis,  84 

mexicana,  84 
kansana,  84 
kennedyi,  84 

klotzschiana,  46,  47,  49,  50,  103,  104 
kruhsiana,  69 
laciniata,  56,  57 
laevigata,  see  levigata 
leibergi,  84 
levigata,  58,  60,  61 
lewisi,  125 
lindheimeriana,  84 
lindleyana,  84,  87,  89 

brevifolia,  84 

coronopus,  84 

legitima,  84 

subdentata,  84 
longifolia,  82 
ludoviciana,  84 

douglasiana,  84,  87 

gnaphalodes,  84 

latifolia,  84 

latiloba,  84 

integrifolia,  84 

serrata,  84 
macallae,  125 

macrobotrys,  46,  48-50,  56,  57,  61,  65,  66,  67, ) 
manca,  125 
mexicana,  84,  87 

bakeri,  84 

silvicola,  84 
michauxiana,  74,  84,  99 
microcephala,  85 
minuta,  61 
monocephala,  112 
muelleri,  85 
nana,  56 
natronensis,  85 
neomexicana,  85 
norvegica,  37,  39,  41,  43,  44,  46-50,  57-65,  67, 

globularia,  58,  59,  64 

glomerata,  46,  58,  60,  64,  65 

heterophyUa,  58,  59,  61,  64 

pacifica,  61 

saxatihs,  43,  58,  60,  61,  64,  67 
nova,  139 
nuttalliana,  117 
obtusa,  85 
pabularis,  85 
pachystachya,  125 
pacifica,  122,  125-127 
palmeri,  33,  47,  48,  135,  155,  156 
parishi,  33,  43,  139,  144,  147 


Artemisia — Continued. 
parryi,  38,  44,  46,  48,  49,  50,  57,  61,  66,  67,  89 
pattersoni,  38,  43,  46,  48,  106,  107,  112-114 
paucicephala,  85 
pedatifida,  38,  44,  47,  48,  61,  114,  115,  130,  131,  132 

133,  134 
persica,  33 

subspineecens,  33 
petrophila,  104 
peucedanifolia,  125 
plattensis,  130 
platyphylla,  73,  84,  85,  99 
pontica,  38,  46,  48,  49,  50,  51,  52,  54,  65 
potens,  85 
prescottiana,  85 
pringlei,  85,  99 
procera,  42,  51 
pudica,  86 
pumila,  86 
purshiana,  39,  86 
angustifolia,  86 
latifolia,  84,  86 
pycnocephala,  125 
pycnostachya,  125 

pygmaea,  42,  47,  48,  132-135,  154,  155 
redolens,  86 
revoluta,  86,  96 
rhizomata,  86 

pabularis,  85,  86 
richardsoniana,  59,  61,  63 
rigida,  33,  41,  47,  48,  133,  135,  149,  153,  154 
ripicola,  125 
rothrocki  139 
rupestris,  106,  107,  109 
rutaefolia,  69,  70 
saxatilis,  58,  60-63 
saxicola,  58,  60,  61 

parryi,  66 
scopulorum,  43,  46,  48,  106,  107,  109,  110,  111,  113, 
114 

monocephala.  111 
scouleriana,  125 
selengensis,  86 
semavinensis,  65 

senjavinensis,  41,  46,  48,  49,  50,  61,  65,  66,  89 
serrata,  84,  86 
silvicola,  84,  86 
spiciformis,  139,  140,  145-147 

longiloba,  140,  145 
spinescens,  32,  33,  38,  44,  47,  48,  114,  132-134,  149, 

340 
spithamaea,  125 

stelleriana,  38,  40,  46,  47,  49,  50,  67,  68,  70 
subglabra,  87 
suksdorfi,  84,  87 
sulcata,  87 
tacomensis,  61 
tanacetifolia,  56 
tenuis,  85,  87 

integerrima,  85,  87 
texana,  87 
tilesi,  49,  87 

arctica,  42,  72,  87 

elatior,  72,  82,  87 

unalaschensis,  87 
tridentata,  19,  37,  42,  44,  47,  48,  55,  104-106,  131- 
134,  135-150,  151-154,  329,  340 


349 


Artemisia — Continued. 
tridentata  —  Continued. 

angustifolia,  139,  140,  143 

arbuscula,  136,  138,  139-141,  143-145,  147,  149 

bolanderi,  136,  139,  141,  145,  148,  149,  151 

nova,  136,  137,  139-146,  149 

parishi,  136,  137,  139,  141-143,  146,  149 

rothrocki,  136,  138,  139-141,  143-147,  149,  152 

trifida,  132,  136,  137,  140,  141,  143-145,  147-149 
153,  154 

typica,  37,  136,  140-149,  151 
trifida,  140,  142,  154 

rigida,  153 
tripartita,  140 
turczaninoviana,  68,  69,  70 
tyrrelli,  61 
unalaskensis,  87 
underwoodi,  87,  92 
variabilis  americana,  125 
vaseyana,  140,  146,  147 
virgata,  109 
viscidula,  151 

vulgaris,  5,  36,  40-44,  46,  47,  49,  68,  70-100,  103, 
150,  155 

americana,  87 

californica,  87,  92 

candicans,  42,  71,  73,  81-83,  85,  88,  90,  97,  99 

discolor,  70,  71,  74„  82-85,  87-92,  97 

douglasiana,  84,  87,  92 

flodmani,  71,  75,  88,  91,  92 

gnaphalodes,  71,  77,  78,  81-88,  90,  91,  94-96,  98- 
100,  120 

heterophylla,  41,  71,  74,  76,  81,  83,  84,  86-88,  90, 
92,  93,  98-100 

lindleyana,  71,  79,  84,  86,  88,  91,  95 

litoraiis,  40,  71,  76,  84,  87,  88,  98 

longifolia,  71,  78,  82-86,  88,  94 

ludoviciana,  71,  76,  78,  81,  82,  84-88,  91,  93-96, 
98-100 

mexicana,  71,  80, 82-88, 91,  96,  99,  156 

reddens,  71,  75, 86, 88, 91, 92 

serrata,  71,  79,  86,  88,  94,  96,  98 

tilesi,  40,  71,  72,  81,  83,  87,  88,  90-94,  97,  100 

typica,  71,  73,  74,  84,  88,  90,  91,  97,  100 

vulgatissima,  87 

vvrighti,  71,  80,  81,  82,  84,  85,  87,  88,  96,  99,  100,  103 
wrighti,  82,  87 
Artemisiastrum,  31-33 

palmeri,  155 
Aster,  7,  13,  158 
Astragalus,  5,  7,  8 
Atriplex,  19,  24,  29,  235-346 
acanthocarpa,  239,  240,  246,  314,  320,  321,  327,  329 

cuneata,  326 
alaskensis,  253,  256 
aldamae,  296 

angustifolia  obtusa,  252,  253 
angustior,  344 
aptera,  343,  344 
arenaria,  258,  294,  296 

argentea,    235,   238,    240,   241,   245,   260,   270,   278, 
279,  282-288,  289,  291,  322,  329 

caput-medusae,  282 

cornuta,  281 

expansa,  283,  284,  285-287,  307,  308 
hillmani,  284,  289 

typica,  283,  284-287 
barclayana,  239,  240,  243,  246,  298,  304,  307,  309, 
313-320,  321,  327,  332,  333 


Atriplex — Continiced. 
barclayana  —  Continued. 

dilatata,  315,  318,  319 

lurida,  315,  316,  318,  319 

magdalenae,  315,  317-319 

palmeri,  315,  318,  319 

sonorae,  315,  316,  318-320 

typica,  315,  316,  317-319 
berlandieri,  344 
bracteosa,  241,  243,  244,  246,  260,  293,  298,  305-308 

309 
breweri,  336 
buxifolia,  325,  326 

californica,  237,  238,  240,  243,  245,  257,  258 
canescens,  19,  131,  149,  235,  236,  240,  243,  246,  280, 
303,  314,  321,  329,  332,  338,  342-346 

angustifolia,  344 

aptera,  343,  345 

garretti,  342,  343,  344,  345 

laciniata,  344 

linearis,  343,  344,  346 

macilenta,  344 

macropoda,  343,  344,  346 

typica,  343,  345,  346 
caput-medusae,  284,  285 
carnosa,  249,  253 
oollina,  339 

confertifolia,  19,   106,  149,   190,  240,  246,  279,  314, 
329,  332,  334,  337,  338-340,  341,  342 

canescens,  339 
confinis,  295,  296 
cordulata,  240,  245,  269-271,  272,  273,  279,  289 

tularensis,  272 
cornuta,  281 
coronata,  238,  240,  241,  245,  271,  288-290 

notatior,  289 

verna,  289 
corrugata,  239,  246,  291,  314,  327,  329,  330,  331,  340 
coulteri,  244, 246, 293, 298, 309,  310,  311 
covillei,  267,  268 
crispa,  296 
cristata,  296 

arenaria,  296 
cuneata,  324,  326 
curvidens,  332 
cyclostegia,  296 
davidsoni,  243,  306 

decumbens,  238,  240,  243,  245,  257,  3 1 1 ,  3 1 2 , 3 13,  330 
depressa,  275 
dilatata,  315 
dimorphostegia,  307 

dioeca,  239,  242-244,  253,  264,  265,  266,  267,  282,  286 
domingensis,  296 
draconis,  267,  269 
drymarioides,  253 
elegans,  241,  245,  246,  280,  293,  298,  300-303,  313 

coronata,  289 

fasciculata,  300,  301,  302 

thornberi,  300-302 

typica,  300,  301,  302 
endolepis,  265 
eremicola,  326 
expansa,  284,  285,  291 

cornuta,  281 

mohavensis,  285 

trinervata,  285 
falcata,  326 
fasciculata,  301 
flagellaris,  262 


350 


Atriplex — Continued. 
fniticulosa,  243,  246,  276,  293,  298,  309,  310,  311,  326 
gardneri,  326 

tridentata,  326 
garreti,  344,  345 
glabriuscula,  250 
glomerata,  296 
gmelini,  253,  256 

zosteraefolia,  253 
gordoni,  326 

graciliflora,  240,  241,  244,  245,  278,  279,  280, 282,  329 
greenei,  273,  274 
greggi,  322 
griffithsi,  336 

halimoideB,  237,  238,  245,  253,  263,  264 
hastata,  249,  253 

litoralis,  253 

patula,  253 
hillmani,  285 
holocarpa,  264 
hortensis,  235-238,  241-244,  247,  248,  257,  268 

atro-sanguinea,  248 

microsperma,  247 

obtusifolia,  247 

rubra,  247 
hymenelytra,  240,  246,  314,  333,  334,  337 
insularis,  317 
joaquiniana,  253 
jonesi,  322 

julacea,  246,  313,  314,  332,  333 
laciniata  americana,  253 
lampa,  261 
lapathifolia,  249,  253 

lentiformie,  19,  239-241,  243,  246,  314,  332,  334-338, 
340,  342,  346 

breweri,  262,  335,  336-338 

griflSthsi,  335,  336,  337 

torreyi,  335,  336,  337 

typica,  335,  337 
leucophylla,  241,  243,  245,  292,  293,  312 
lindleyi,  264 
linearis,  344,  345 

linifolia,  244,  246,  293,  298,  307,  308,  309 
litoralis,  251,  253 
lurida,  313,  316 
macropoda,  344,  345 
magdalenae,  315 

maritima,  245,  255,  258,  259,  260 
matamorensis,  238,  243,  246,  312,  313,  330 
microcarpa,  244,  246,  293,  298,  303,  304,  306,  307 
minuscula,  276 
mohavensis,  285 

monilifera,  239,  242,  245,  265,  266 
mucronata,  296 
nnuricata,  296,  305 
nelsoni,  291 
neomexicana,  326 
nitens,  247,  248 
nodosa,  285 

nuttalli,  190,  240,  243, 245, 246,  291,  314,  321, 322-329, 
330,  340,  345 

anomala,  326 

buxifolia,  323,  325,  328,  329 

corrugata,  330 

cuneata,  323,  324,  325,  328,  329 

falcata,  323,  325,  327-329 

gardneri,  323, 324,  326-328 

tridentata,  323,  324,  327,  328 


Atriplex — Continued. 
nuttalli — Continued. 

typica,  323,  326-328 

utahensis,  326 
oblanceolata,  326 
obovata,  246,  314,  321,  322,  327,  329,  345 

tuberata,  322 
occidentalis,  345 
odontoptera,  345 
oppositifolia,  313 
orbicularis,  337 
ovata,  265 
pabularis,  327 

eremicola,  327 
pacifica,  303 
palmeri,  315 

parishi,  241-243,  245,  270,  273,  274-276 
parryi,  240,  246,  314,  341,  342 
parvifolia,  296 
patula,  235,  237,  238,  241,  243,  244,  248-256 

alaskensis,  249,  252,  253,  256 

bracteata,  256 

glabriuscula,  249,  250,  255,  259,  260 

hastata,  249,  253-256 

litoralis,  249,  251,  254-256 

obtusa,  249,  252,  256 

spicata,  249,  251,256 

subspicata,  254 

typica,  249,  250,  251,  255,  256 

zosteraefolia,  249,  252,  253,  256 
pentandra,  238-240, 243,  246,  293,  294-300,  302,  307 

arenaria,  260,  294,  298,  299 

confinis,  294,  295,  296,  298,  300 

muricata,   243,   294,   295,  298-300,  302,  304,  307, 
309,311 

typica,  243, 294, 295, 296-300 
philonitra,  291 
phyUostegia,  236,  238,  239,  242-244,  265,  266-269, 

286 
polycarpa,  19,  240,  246,  303,  308,  314,  318,  321,  331- 

333,  334,  338,  341,  342,  346 
polygama,  308 
prostrata,  311 

poweUi,  238, 240, 241, 243,  245,  285,  290,  291, 322,  329. 
pringlei,  321 
pueblensis,  297 
purshiana,  254 

pusilla,  238,  239,  241,  245,  270,  272,  273,  274,  276 
radiata,  305 
rosea,  235,  238,  241,  245,  258,  259-261,  273,  308,  329 

arenaria,  258 
rosei,  317 

rydbergi,  282,  285-287 
sabulosa,  258,  322 

saccaria,  240,  241,  245,  278,  280-282,  329 
sagittata,  247,  248 
saltonensis,  301 
semibaccata,  235,  237,  238,  240,  241,  245,  262,  263, 

312 
serenana,  307 
siberica,  235 
sonorae,  316 
sordida,  289 
spatiosa,  259 
spicata,  251,  259 

lagunita,  254 
spinifera,  240,  246,  308,  314,  340,  341,  342 
spinosa,  339 


351 


A  triplex — Continued. 

subconferta,  339 

subdecumbens,  276-278 

subspicata,  254 

suckleyana,  265 

tampicensis,  297 

tatarica,  245,  259,  260,  261 

tenuissima,  245,  270,  273,  274 

tetraptera,  345 

texana,  297 

thoraberi,  302 

torreyi,  337 

tridentata,  324,  327 

trinervata,  285 

truncata,  238,  240,  241,  243,  245,  276-278,  279,  281, 
282 
saccaria,  281 
stricta,  276,  277 

tuberculata,  297 

tularensis,  245,  270,  271,  272,  273 

umbellata,  293 

vema,  289 

vesicaria,  264 

volutans,  286 

wardi,  297 

watsoni,  311 

woKi,  245,  272,  273,  278,  279 

wrighti,  243,  244,  246,  293,  298,  304,  305,  307 

zosteraefolia,  254 
Australian  Saltbush,  262 
Avena  fatua,  56,  312 
Axyris  pentandra,  294,  297 
Baeria  chrysostoma,  33,  312 
BaUscale,  309 
Beach  Sage  wort,  67 
Berberis  aquifolium,  71 
Beta,  235 

Biennial  Sagewort,  101 
Bigelovia,  157-160,  174 

albida,  193 

bigelovi,  218 

bolanderi,  202 

ceruminosa,  218 

collina,  218 


douglasi,  181,  184 

lanceolata,  184 

latifolia,  184 

puberula,  184 

pumila,  184 

serrulata,  184 

spathulata,  184 

stenophylla,  183,  184 

tortifolia,  184 
dracunculoides,  218 
glareosa,  217,  218 
glauca,  185 
graveolens,  218 
albicaulis,  218 
appendiculata,  218 
glabrata,  218 
hololeuca,  211,  218 
latisquamea,  212,  218 
greenei,  190,  191 
howardi,  202 

attenuata,  201,  202 

nevadensis,  202 
juncea,  170,  216,  218 


Bigelovia — Continued. 

lanceolata,  185 

leiosperma,  218 
abbreviata,  218 

linifolia,  185 

menziesi  scopulorum,  179 

missouriensis,  218 

mohavensis,  216,  218 

nevadensis,  202 

nudata,  157 

paniculata,  175,  176 

parryi,  202 

pulchella,  194 

pyramidata,  197 

teretifolia,  177 

turbinata,  217,  218 

vaseyi,  179,  180 

viscidiflora,  185 
Birdfoot  Sagebrush,  131 
Black  Sage,  150 
Blitum,  235 
Boreal  Sagewort,  57 
Bouteloua,  206 

gracilis,  105,  192,  195,  197 
Bractscale,  305 
Brittlescale,  274 
Broadscale,  321 
Bromus  maximus,  56 
Bud  Sagebrush,  132 
Burscale,  320 
Bush,  Golden,  174 
Calligonum  canescens,  343,  346 
Carex,  65 

Cattle  Spinach,  332 
Ceanothus,  55 
Centaurea  meUtensis,  101 
Cerastium  viscosum,  10 
Cereus,  332 
Chaenactis,  33 

carphoclinia,  33 
Chamartemisia,  31,  32 
Chenopodium,  235 

subspicatum,  249,  254 

zosteraefolium,  253,  254 
Chondrophora,  158-160,  180 

nudata,  157 
Chrysanthemum,  35 
Chrysocoma,  157,  174,  219 

dracunculoides,  218,  219 

graveolens,  189,  214,  218,  219 

nauseosa,  209,  213,  219,  226 
Chrysopsis,  13 

Chrysothamnopsis,  Sect.,  160,  174 
Chrysothamnus,  24-26,  29,  157-234,  340 

affinis,  202 

attenuatus,  202 

albidus,  159,  161,  163,  165,  166,  172,  175,  192,  193 

angustus,  219,  227 

appendiculatus,  219 

arizonicus,  219 

asper,  200,  202 

attenuatus,  202 

bailey  i,  194 

bakeri,  180 

bigelovi,  194,  219 

bloomeri,  158 

bolanderi,  160,  202 


352 


C  hrysothamnus — Continued. 
californicus,  219 

occidentalis,  214,  219,  227 
ceruminosus,  191,  220 
collinus,  220 
concolor,  220 
confinis,  220,  227 
consimilis,  215,  220 

depressus,  161,  162,  166,  169,  175,  194,  195-197 
douglasi,  185 
dracunculoides,  220 
elatior,  194 
elegans,  183,  185 
falcatus,  220,  227 
filifolius,  191 
formosus,  220 
frigidus,  220,  226 

concolor,  220 
glareosus,  220 
glaucus,  1S5,  186 
gnaphalodes,  220 
gramineus,  158,  161-164,  166,  169,  171,  172,  175 

178,  179,  180 
graveolens,  220 

glabrata,  220 
greenei,  161-163,  166,  172,  175,  180,  186,  190-192. 
193 

filifolius,  190-192 

typicus,  190,  191,  192 
howardi,  167,  202,  228 
humilis,  182,  185 
junceus,  220 

laetevirens,  170,  220,  227 
lanceolatus,  181,  185 
laricinus,  191 
latifolius,  185 
latisquameus,  220 
leiospermus,  220 
leucocladus,  185 
linifolius,  184,  185 
macouni,  220 
marianus,  164,  185 
mohavensis,  220 
monocephalus,  200,  202 
moquianus,  220 

nauseosus,  5,  24,  25,  149,  161,  162,  164-176,  178,  190, 
191,  195,  197,  202,  203,  206,  209-234 

albicaulis,  210,  212,  221,  223,  226,  228,  229,  231 

bernardinus,  166,  168,  210,  214,  221,  223,  227,  232 

bigelovi,  164,  167,  195,  206,  210,  217,  221,  223,  224, 
229 

californicus,  221 

ceruminosus,  210,  216,  221,  223,  228 

consimUis,  155,  166,  171,  174,  193,  210,  215,  221, 
223,  227,  228-232,  234,  269,  278,  329 

frigidus,  221 

glareosus,  164,  210,  217,  221,  223,  229 

gnaphalodes,  167,  168,  171,  173,  202,  210,  211,  221, 
223,  225,  229,  230,  234 

graveolens,  171,  172,  173,  210,  214,  221,  223-229, 

hololeucus,  167,  170,  171,  173,  202,  210,  211,  221, 

223,  225,  226,  229,  230,  234 
junceus,  106,  167,  210,  216,  221,  223,  224,  228,  229 
latisquameus,  210,  212,  221,  223,  226,  231 
leiospermus,  164,  173,  178,  210,  217,  221,  223,  229 
mohavensis,  166,  210,  216,  221,  223,  228,  233 
occidentalis,  210,  213,  221,  223,  226,  227 


Chrysothamnus — Continued. 
nauseosus — Continued. 
oreophilus,  221 
pinifoUus,  166,  171,  208,  210,  215,  221,  223,  227- 

229,  232,  234 
plattensis,  221,  225 
salicifolius,  210,  213,  221,  223,  226 
speciosus,   166,   167,   173,  210,  211,  221,  223-227, 

229,  230 
turbinatus,  167,  210,  217,  223,  224,  228,  229,  234 
typicus,  167,  203,  210,  213,  223,  224,  226,  231 
viridulus,  166,  167,  171,  173,  174,  210,  215,  221, 
223,  227-229,  233,  234 
nevadensis,  202 
monocephalus,  202 
vulcanicus,  202 
newberryi,  202,  206 
occidentalis,  221,  227,  231 
oreophilus,  221,  227 

artus,  221 
orthophyllus,  221 
pallidus,  221 

paniculatus,  161-163,  166,  172,  175,  176,  177,  178 
parryi,  160-162,  164-169,  172,  173,  175,  178,  193, 
197,  198-209,  222,  224 
asper,  169,  198,  200,  202-207 
attenuatus,  169,  198,  201,  202-204,  206,  208 
bolanderi,  198,  199,  204-207 
howardi,  169,  198,  201,  202-206,  208,  209 
imulus,  198,  200,  204,  205,  207 
latior,  167,  197,  198,  199,  204,  205,  207,  224 
monocephalus,  169,  198,200,204,  205,206,208,209. 
nevadensis,  169,  198,  201,  202-206,  208 
typicus,  198,  202-206,  209 
vulcanicus,  169,  198,  200,  203,  204,  206,  207 
patens,  222,  227 
pinifolius,  170,  215,  222 
plattensis,  222,  226 
puberulus,  185 

pulchellus,  159,  161,  162,  164,  166,  169,  172,  175, 
193,195,  196,  197 
baileyi,  194,  195 
elatior,  194,  195,  196 
typicus,  194,  195 
pulcherrimus,  222,  226 

fasciculatus,  222 
pumilus,  158,  182,  185,  206 
acuminatus,  191 
euthamoides,  185 
latus,  185 
varus,  185 
pyramidatus,   161,  162,  164-167,   172,  175,  197,  198, 

224,  228 
salicifolius,  213,  222 
scoparius,  191 
serrulatus,  185 
speciosus,  170,  212,  222 
albicaulis,  170,  212,  222 
arizonicus,  222 
gnaphalodes,  211,  222 
latisquameus,  222 
plattensis,  222 
stenolepis,  183,  185,  186 
stenophyllus,  186 

teretifolius,  161,  162,  166,  168,  172,  175,  176-178 
tortifolius,  186 
tortuosus,  222 
turbinatus,  222 


353 


Chrysothamnus — Continued. 

vaseyi,  161-166,  168,  172,  175,  178,  179,  180,  186, 
189,  191 

virens,  170,  222,  227 

viscidiflorus,  149,  161-166,  168-172,  175,  180-190, 
191,  192,  197,  206 
elegans,  168,  181,  183,  188,  189 
humilis,  181,  182,  188,  197 
lanceolatus,  181,  185-189 
latifolius,  181,  184,  186,  188,  189 
linifolius,  168,  172,  181,  184,  188-190 
puberulus,  181,  182,  187-190 
pumilus,  180,  181,  182,  186-190,  197 
serrulatus,  186,  189 
stenophyllus,  181,  183,  186-191 
tortifolius,  186 
typicus,  169,  181,  183,  180-189 

vulcanicus,  200,  203 

wyomingensis,  203 
Chrysothamni*,  Sect.,  174 
Claytonia,  7 
Clover,  Poison,  331 
Coast  Sagebrush,  19,  53 
Common  Sagebrush,  150 
Crinitaria  viscidiflora,  157,  181,  183,  186,  187 
Crossostephium,  31-33,  36,  54,  55,  131 

artemisioides,  32,  54 

californicum,  54 

insulare,  53 
Crownscale,  288 
Cynodon  dactylon,  307 
Dalea  scoparia,  131 
Desert  Holly,  333 
Dichospermum,  Sect.,  237 
Distichlis,  258,  269,  271-273,  276,  278,  287,  293,  307 

spicata,  307,  310,  312,  338 
Dodecatheon,  13 
Dotscale,  303 
Draba  verna,  10 

Dracunculus,  Sect.,  32-37,  40,  46,  114 
Dragon  Sagewort,  19,  115 
Dwarf  Sagewort,  110 
Elymus  condensatus,  193,  272 
Encelia,  334 

frutescens,  176 
Endolepis,  236,  238,  239,  265-268 

covillei,  267,  268 

dioeca,  265 

monilifera,  266 

ovata,  265 

phyllostegia,  267 

suckleyi,  265,  267 
Epilobium  spicatum,  71 
Eremocarpus,  341 
Ericameria,  Sect.,  154,  157-160,  162,  163,  176 

diffusa,  159,  163 

paniculata,  176 
Erigeron,  65 

uniflorus,  HI 
Eriochloa  polystachya,  305 
Eriodictyum  tomentosum,  55 
Eriogonum,  13,  265,  346 

fasciculatum,  55 

divaricatum  282 

inflatum,  329 
Erodium  cicutarium,  308 
Eschscholtzia,  312 
Estafiat,  56 


Estragon,  120 

Euartemisia,  35 

Euatriplex,  Subgenus,  237-239,  241,  243 

Euphorbia,  7 

Eurotia  lanata,  149 

Eutettix  tenella,  260,  263,  271,  276,  287,  290,  308,  333, 

341 
Field  Sagewort,  19,  120 
Flat  Sagebrush,  104 
Fleshscale,  262 
Forest  Sagewort,  69 
Fouquiera,  332,  334 
Fragaria  vesca,  71 
Frankenia,  271,  276,  341 
Franseria,  334 

bipinnatifida,  293 
Frasera,  13 
Garden  Orache,  247 
Garden  Sagebrush,  49 
Gardenscale,  247 
Gastridium,  341 
Gentiana,  5,  7 
Geranium  caespitosum,  71 
Gilia,  7 

Grossularia  grossularia,  18 
Golden  Bush,  174 
Grayia,  340 

spinosa,  149 
Gutierrezia,  13,  190,  206 

sarothrae,  106,  110,  149 
Habenaria,  7 
Hair  Tonic,  120,  129 
Haplodiscus,  Sect.,  158,  179 
Haplopappus,  7,  19,  154,  157-160,  162,  163,  176,  258 

arborescens,  158 

brachylepis,  159 

discoideus,  160 

monactis,  158 

pygmaeus.  111 
Hastatae,  Sect.,  237 
Heartscale,  269 
Heleocharis,  19 
Helianthus  annuus,  271 
Heliotropium  curassavicum,  271 
Hemizonia  pungens,  271,  276 
Henningsocarpum,  18 
Hesperodoria,  179 
Hilaria  jamesi,  105 
Hoary  Sagebrush,  19,  150 
Holly,  Desert,  333 
Hollyscale,  333 
Homalobus,  8 

Hyraenoclea  salsola,  176,  178 
Indian  Hair  Tonic,  120 
Isocoma,  Sect.,  158,  179 

scopulorum,  179 
Juncus,  65 

Kalstroemia  grandiflora,  305 
Kochia,  149 

dioeca,  264,  265,  267 
-  vestita,  149,  340 
Krvnitzkia,  13 

Larrea,  55,  176,  178,  332,  334,  342 
Layia  platyglossa,  312 
Leaf-hopper,  308 
Lenscale,  19,  334 
Lepidospartum  squamatum,  176 


354 


Linosyris,  158 

albicaulis,  222 

bigelovi,  170,  217,  222 

bolanderi,  199,  203 

ceruminosa,  216,  222 

depressa,  196 

graveolens  glabrata,  222 

howardi,  201,  203 
nevadensis,  201,  203 

lanceolata,  186 

parryi,  198,  199,  203 

pulchella,  194 

pumila,  186 

serrulata,  186 

teretifolia,  177 

viscidiflora,  186 
latifolia,  184,  186 

paniculata,  176 
puberula,  182,  186 
Bemilata,  186 
Lotus,  7 

glaber,  55 
Lupinus,  13 

argenteus,  208 
Macronema,  Sect.,  160 

bolanderi,  203 
Madia  sativa,  101 
Matscale,  330 
Medicago  hispida,  101 
Mesembryanthemum  nodiflorum,  2 
Mimulus,  65 
Montia  perfoliata,  10 
Moundscale,  322 
Mugwort,  70 

Muhlenbergia  pungens,  195 
Nauseosi,  Sect.,  160,  161,  162-166 
Obione,  235-239,  241,  243 

acanthocarpa,  320,  321 

arenaria,  297 

argentea,  286 

barclayana,  313,  316 

berlandieri,  345 

bracteoBa,  306,  307 

canesoens,  345 

confertifolia,  338,  339 

coulteri,  310 

crispa,  295,  297 

cristata,  297 

elegans,  300,  302 
radiata,  302,  305 
tuberculosa,  297 

gardneri,  324,  327 

hymenelytra,  334 

kunthiana,  297 

lentiformis,  335,  337 

leucophylla,  292 

linifolia,  308 

microcarpa,  303,  304 

muricata,  235,  297 

occidentalis,  345 
angustifolia,  345 

phyllostegia,  266,  267 

poiycarpa,  331,  332 

polygama,  308 

pusilla,  272,  273 

radiata,  302 

spinosa,  339 

suckleyana,  236 


Obione — Contintied. 

tetraptera,  345 

torreyi,  336,  337 

truncata,  277 
Obionopsis,  Sect.,  239,  255,  259 
Oenothera,  7 

bistorta,  312 
Old  Man,  51,  56 
Oligosporus,  34 

mexicanus,  87 

pycnoeephalus,  125 
Opuntia,  334 
Orache,  Garden,  247 

Red,  259 

Spear,  248 
Parkinsonia,  332 
Parryani,  Sect.,  161 
Pedicularis  parryi.  111 
Pentstemon,  13,  346 
Petradoria,  158,  178 

pumila,  180 
Phacelia,  13 

Picrothamnus,  31-33,  114,' 133 
Pigmy  Sagebrush,  154 
Pinus,  5 

Platystemon,  312 
Poison  Clover,  331 
Poliomintha  incana,  131 
Polygonum,  7 
Potentilla,  13 
Prairie  Sagewort,  108 
Prosopis,  332,  338,  346 
Pterochiton,  235,  236 

canescens,  345 

occidentale,  345 
Pulchelli,  Sect.,  160,  161,  162-166,  168,  169,  178,  180 
Punctati,  Sect.,  157,  159,  160,  161,  162,  163,  165,  166, 

169,  171,  193 
PusiUae,  Sect.,  240,  270-272,  279 
Rabbit-brush,  174 
Radlkofertoma,  18 
Ranunculus,  7 
Rhopalomya,  131 
Red  Orache,  259 
Redscale,  259 
Rhus  integrifolia,  55 
Ribscale,  290 
Rillscale,  264 
Robinia,  7 
Sage,  Black,  150 
Sagebrush,  19,  135 

Birdfoot,  131 

Bud,  132 

Coast,  19,  53 

Common,  150 

Flat,  104 

Garden,  49 

Hoary,  19,  150 

Pigmy,  154 

Sand,"  19,  130 

Scabland,  145 

Stiff,  153 

Tall,  155 
Sagewort,  19,  70 

Absinthe,  106 

Alpine,  112 

Annual,  102 

Beach,  67 


355 


Sagewort — Continued. 

Biennial,  101 

Boreal,  57 

Dragon,  19,  115 

Dwarf,  110 

Field,  19,  120 

Forest,  69 

Prairie,  108 
Salicornia,  258,  271,  272,  338,  340 
Salix,  13 
Salsola,  236,  279,  287,  291,  322,  341 

dioeca,  265 
Saltbush, 

Australian,  262 

spiny,  338 
Salvia,  346 


mellifera,  55 

nivea,  55 
Sand  Sagebrush,  19,  130 
Sarcobatus,  149,  190,  193,  229,  269,  273,  291,  322,  329, 

338,  340,  346 
Saxifraga,  7 

Scabland  Sagebrush,  145 
Schweinfurthafra,  18 
Sclerocalymna,  Sect.,  239,  259 
Seascale,  292 
Seneeio,  13 

Seriphidium,  33-39,  46,  50,  134,  135 
Shadscale,  19,  338,  342 
Silverscale,  282 
Smallscale,  272 
SoUdago  pumila,  178 
Southernwood,  51 
Spear  Orache,  248 
Spearscale,  248 
Sphaeromeria,  31,  32,  35 
Spinach 

Cattle,  332 

French,  248 


Spinachia,  235 
Spinescale,  340 
Spiny  Saltbush,  338 
Spirostachys,  272,  290,  338 
Sporobolus,  148,  338 

airoides,  190,  278,  291,  322 

asperifolius,  272 

cryptandrus,  105 
Spuriae,  Sect.,  174 
Stiff  Sagebrush,  153 
Stipa,  55,  206 

eminens,  56 

setigera,  56,  312 
Suaeda,  262,  279,  287,  322,  329,  338 
Suckleya,  236 
Sugar-beet,  308 

Symphoricarpus  symphoricarpus,  18 
Tall  Sagebrush,  155 
Tanacetum,  31,  32,  35,  142 

bipinnatum,  31 

compactum,  31 

huronense,  31 
Tarragon,  120 
Tetradymia,  340 

spinosa,  149 
Teutliopsis,  Sect.,  237 
Thalictrum  fendleri,  71 
Trichostema,  341 
Trifolium,  7 
Twoscale  280 

Typici,  Sect.,  160,  161,  162-166,  168,  169,  172,  193 
Vesicarpa,  31,  32 
Wedgescale,  276 
Wheelscale,  300 
Wingscale,  19,  342 
Wormwood,  108 

Roman,  52 
Yucca,  131,  176 


University  Libraries 


